Patent Publication Number: US-6659506-B1

Title: Index system

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates in general to publications using features for retrieval of information, especially the use of an index system for booklets and like publications. 
     DESCRIPTION OF RELATED ART 
     Big steps forward have been achieved in this relatively crowded field. The mass of information has created an urgent need for clear categorization of information to allow fast and easy retrieval. However, there are serious limitations in the known index svstems, which limit their utility. Despite important advances, the present index systems still suffer from drawbacks which are seemingly inherent in the approaches employed. Attempts have been made to solve or at least alleviate these drawbacks. For example, U.S. Pat. No. 5,630,626 granted on May 20, 1997 to Harper for an Information Guide describes a system using leaves attached to a backing sheet along mutually spaced fold lines extending parallel to one another across the backing sheet. The leaves are turnable about the fold lines from first positions in which they lie overlapped on the backing sheet, to a position where they lie overlapped beyond the backing sheet The information text has first text portions with markings that relate to second text portions having corresponding information. By using the markings, the reader is able to go from a first text discovered while reading to a second text that provides more related information. Harper&#39;s patent incorporates several shortcomings. First, optimal use of the product requires that the proposed information guide be placed on a surface or otherwise held by both hand for stability. Second, since use is made of only individual leaves rotating around their own axes, the total quantity of information provided by such a booklet is restricted. Third, the product has use only primarily in a notepad orientation rather than as a normal book, thereby limiting its use. Fourth, the product is not provided with means for hierarchical grouping of information. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Although the characteristic features of this invention will be particularly pointed out in the claims, the invention, and the manner in which it may be made and used, may be better understood by referring to the full descriptions taken in connection with the accompanying drawings forming part thereof, wherein like reference numerals form like parts. 
     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting but merely as a basis for the claim and as representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a simple unit having a left leaf and a right leaf, with the lower edge of left leaf upwardly spaced with respect to lower edge of right leaf; 
     FIG. 2 shows a unit wherein the right leaf has its upper edge downwardly spaced with respect to the corresponding edge of left leaf; 
     FIG. 3 shows a unit wherein the right leaf has its outside edge outwardly spaced with respect to the corresponding edge of left leaf; 
     FIG. 4 shows a first embodiment with a cover and offset leaves attached to it: 
     FIG. 5 shows an embodiment with two units in mirror image; 
     FIG. 6 shows an embodiment with a cover with a plurality of left leaves and right leaves provided with cuttings for exposing identifying indicia: 
     FIG. 7 provides an embodiment with folding flaps at the extremities of the cover: 
     FIG. 8 shows diagrammatically a multiple cover to which are attached on both sides several successive units; 
     FIG. 9 shows in diagrammatic form one entity formed by parallel leaves and spaced axes; 
     FIG. 10 shows in diagrammatic form one entity formed by parallel leaves and spaced axes; 
     FIG. 11 shows in diagrammatic form one entity formed by parallel leaves and spaced axes; 
     FIG. 12 shows in diagrammatic form a combination of entities, each formed by parallel leaves and spaced axes; 
     FIG. 13 shows an embodiment using a singular axis about which groups of leaves of different extensions rotate to expose marginal portions; 
     FIG. 14 shows diagrammatically a combination of superposed entities; 
     FIG. 15 shows diagrammatically a combination of superposed entities; 
     FIG. 16 shows diagrammatically a combination of superposed entities; 
     FIG. 17 shows diagrammatically a combination of superposed entities; 
     FIG. 18 shows diagrammatically a combination of superposed entities; 
     FIG. 19 provides an embodiment with superposed entities and spaced axes of rotation; 
     FIG. 20 shows an embodiment with superposed entities having their folding axes on front and back covers, respectively; 
     FIG. 21 shows an embodiment in notepad form with superposed entities; 
     FIG. 22 shows an embodiment in a note pad form with several superposed entities; 
     FIG. 23 shows an embodiment with multiple entities, joined to front and back covers, formed from a single strip of material; and 
     FIG. 24 shows an embodiment with multiple entities, joined to front and back covers, formed from a single strip of material. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, in FIG. 1 a simple unit for an indexing system generally shown as  10  is illustrated in an open position. Simple unit  10  comprises two leaves, a left leaf  12  and a right leaf  14 , integrally formed, or constituted from two separate sheets. Left leaf  12  and right leaf  14  are each formed with a pair of opposing, mutually parallel, transverse edges, specifically an upper edge  16  and  16 ′, respectively, and a lower edge  18  and  18 ′, respectively. Left and right leaves  12  and  14  are each also formed with an outer longitudinally extending edge, specifically a side edge  20  and an opposing side edge  20 ′. Leaves  12  and  14  each have, when they are formed from separate sheets, an inside edge  22  and  22 ′ respectively. When a left leaf  12  is integral with a right leaf  14 , a fold line replaces the above edges  22  and  22 ′. Left and right leaves  12  and  14 , when constituted by separate leaves, are bound together along inside edges  22  and  22 ′. Left leaf  12  has its lower edge  18  upwardly spaced with respect to lower edge  18 ′ of right leaf  14 . Thus, when left leaf  12  is superposed on right leaf  14 , a marginal portion  24  of right leaf  14  remains uncovered and visible. On marginal portion  24 , an indicia marking zone  26  is provided. There is printed matter  28  on each of left leaf  12  and right leaf  14 . The printed information on indicia marking zone  26  and in the text of printed matter  28  is identically oriented for easy reading. 
     In a variant  20  (see FIG. 2) of the unit  10  of FIG. 1, upper edge  16  of left leaf  12  is upwardly spaced with respect to upper edge  16 ′ of right leaf  14 . Correspondingly, marginal portion  24  will be located on the top of left leaf  12  and visible when right leaf  14  overlies left leaf  12 . 
     In another variant  30  (see FIG. 3) of the unit  10  of FIG. 1, side edge  20  of left leaf  12  is inwardly spaced with respect to opposing side edge  20 ′, so that when left leaf  12  is superposed on right leaf  14 , a marginal portion  24  extending from opposing side edge  20 ′ remains visible. Correspondingly, left leaf  12  can be the mirror image of right leaf  14 . Thus, the marking portion  24  becomes visible either on the bottom, top or side of left leaf  12  when right leaf  14  is superimposed on the latter. 
     In another embodiment of the present invention, depicted in FIG. 4, a booklet having an indexing system generally shown as  40  is illustrated in an open position.,Unit  40  comprises five left leaves  12  and five right leaves  14 , each left leaf  12  being continued by its associated right leaf  14  and a folding line  32  separates the former from the latter. Along folding line  32 , the left and right leaves are bound and attached to a cover constituted of a left cover  34  and a right cover  36 , which in the present case are integrally formed. All the left and right leaves  12  and  14  are of identical dimensions. 
     Left cover  34  and right cover  36  are each formed with a pair of opposing, mutually parallel transverse extremities, specifically an upper extremity  38  and  38 ′ respectively and a lower extremity  40  and  40 ′ respectively. Left and right covers  34  and  36  are each also formed with an outer longitudinally extending extremity, specifically a side extremity  42  and an opposing side extremity  42 ′. 
     Left leaf  12 , adjacent to left cover  34  has its upper edge  16  substantially coincident with the upper extremity  38  of left cover  34 . The same left leaf  12  has its lower edge  18  so upwardly spaced with respect to the lower extremity  40  of left cover  34 , that when a left leaf  12  is placed together on subsequent leaves of the unit on the right cover  36 , it becomes a right leaf  14 , and the marginal portions  24  of all subsequent now-right leaves  14  are visible. 
     Right leaf  14  adjacent to right cover  36  has its lower edge  18 ′ substantially coincident with the lower extremity  40 ′ of right cover  36 . The same right leaf  14  has its upper edge (not visible on the drawings) downwardly spaced with respect to upper extremity  38 ′ of right cover  36 ; that right leaf  14  adjacent to right cover  36  is placed so that it has its lower edge  18 ′ substantially coincident with the lower extremity  40 ′ of the right cover  36 . When the same right leaf  14  =adjacent back cover  36  is rotated towards left cover  34 , it becomes a left leaf  12 . This now-left leaf  12 , as the subsequent left leaves  12  beneath it, reveals all marginal portions  24  of all subsequent left leaves  12  between it and front cover  34 . 
     In the open position of the unit, each left leaf  12  has a front face  43  and a back face  43 ′. Correspondingly, also in the open position, each right leaf  14  has a front face  44  and a back face  44 ′. Printed matter  28  is disposed on front faces  43  and  44  and on back faces  43 ′ and  44 ′. Each left leaf  12 , in the open position of the unit, is provided on its upper part with a marginal portion  24  with its indicia marking zone  26 . When a left leaf  12  is rotated completely to the right, to lie on its front face  43 , a marginal portion  24  with its indicia marking zone  26  is disposed and visible on its back face  43 ′ and another marginal portion  24  with its indicia marking zone  26  is disposed and visible at the lower part of face  44  of right leaf  14  (former left leaf  12 ). Thus, when a left leaf  12  is rotated completely to the right, it becomes a right leaf  14 , with a front face  44 , which is a former back face  43 ′. 
     The printed material on indicia marking zone  26  and in printed matter  28  is identically oriented for easy reading. 
     In the operation, unit  40  is opened and use is made initially of indicia marking zone  26 , disposed at the upper part of front face  43  of each left leaf  12 . 
     Each indicia marking zone  26  contains a number and a commencement arrow, the numbers starting consecutively from left leaf  12  adjacent to left cover  34 . In addition to the number and commencement arrow, each indicia marking zone  26  is provided with a brief description of printed matter  28  contained on all above faces. After the reader considers the information contained in printed matter  28  on front face  43 , he/she is made aware of additional information available by the fact that the same numeral is contained in indicia marking zone  26  situated at the upper part of face  44  of right leaf  14 . The additional information is contained in printed matter  28  of the above face  44 . On indicia marking zone  26  situated at the bottom of face  42 ′ of right leaf  14  there is indicated the number as above and a terminating arrow having a direction opposed to the commencement arrow. The brief description on indicia marking zone  26  situated at the bottom of face  44  is consistent with the brief description on indicia marking zone  26  situated at the top of face  43  of left leaf  12 . All marginal portions  24  containing the same number have the same background color(s) on corresponding left and right leaves  12  and  14 . Left leaf  12 , adjacent to left cover  34 , on its back face  43 ′, and right leaf  14  adjacent to right cover  36 , on its back face  44 ′, are not provided with marginal portion  24 . 
     In another embodiment of the present invention, depicted in FIG. 5, an indexing system shown as  50  is presented in an open position. Booklet  50  comprises basically two units  40 , each unit  40  being so disposed that it represents the mirror image of the other one. In the open position, a cover is formed from first front cover  46  and a first back cover  48 , and is continued as a mirror image by a second back cover  48 ′, followed by a second front cover  46 ′. In the closed position, the first back cover  48  is situated on the top of the booklet  50  and second back cover  48 ′ forms the bottom of booklet  50 . 
     Booklet  40  situated at the left has its own folding line  56 , while booklet  40  situated at the right has its own folding line  58 . 
     First back cover  48  terminates with a folding line  52  followed by a second folding line  54  at the beginning of second back cover  48 ′. Thus, a space is created for accommodating a number of left and right leaves  12  and  14  belonging to two units  40 . Printed matter  28  is disposed on front faces  43  and  44  and on back faces  43 ′ and  44 ′ of left leaves  12  and right leaves  14 , respectively. As in the previous embodiment (FIG.  4 ), each left leaf  12 , in the open position of booklet  50 , is provided on its upper part with a marginal portion  24  with its indicia zone  26 . When any left leaf  12  is rotated completely to the right, it becomes a right leaf  14  which has a marginal portion  24  with its indicia marking zone  26  disposed at its lower part, and another indicia marking zone  26  disposed at its upper part. 
     When all left leaves  12  are completely rotated to the right, and, thus, themselves become right leaves  14 , each succeeding right leaf  14  after the top one is sequentially downwardly displaced so as to reveal its marginal portion  24 . 
     If the information contained in several succeeding leaves  12  or  14  is required to be compartmentalized from information contained in following leaves, for example to indicate a new chapter, a dividing marginal portion  24   a  is intercalated between the above several leaves succeeding leaves  12  and the following ones. Dividing margin portion  24   a  is always followed by a regular marginal portion  24  belonging also to subsequent leaf related to the same subject. In order to distinguish dividing margin portion  24   a  from a margin portion  24 , the former has an increased size in height. 
     Also as in the previous example (FIG.  4 ), each right leaf  14 , in the open position of booklet  50 , is provided with an indicia marking zone  26  on its front face  44 , at its lower part. If the information contained in several right leaves  14  requires to be compartmentalized from the succeeding information contained in the following right leaves  14 , for example in chapters, a dividing marginal portion  24   a  is also intercalated. 
     Each indicia marking zone  26 , in the present embodiment, contains a capital letter followed by a numerical marking. A section or a chapter containing grouped information will be represented by several leaves  12  or  14 , each leaf using the same capital letter followed by a same number for one or more faces containing related subject matter. As stated before, use is made of dividing marginal portion  24   a . On the latter is shown a capital letter identical to that found on each succeeding leaf that belongs to the same section or chapter. 
     As in the previous embodiment (FIG.  4 ), each indicia marking zone  26  contains a commencement arrow, in the present case, after the capital letter and the numeral situated on left leaves  12  of booklet  50  in open position. Indicia marking zone  26  includes a brief description of printed matter  28  contained on the same front face  43  and  44 , respectively. There are two distinct colors on each marginal portion  24 . One color identifies dividing marginal portion  24   a , the other color is identical to a color assigned to a marginal portion  24 . 
     As stated before, booklet  50  contains basically two units  40 . The information in first unit  40  is continued by that in second unit  40 . When booklet  50  is used, a person searching for particular information will start by opening booklet  50  and, then, regardless of the position in which booklet  50  is open, all the necessary indexed information is visible at once allowing the person to easily find the location of the desired material. 
     In the open position, booklet  50  reveals at a glance different dividing marginal portions  24   a . The reader establishes in which of those dividing marginal portions  24   a  his/her required information is to be found by reading the brief descriptions thereof. After identifying the specific information from the brief description of the dividing marginal portions  24   a , the reader continues by identifying in which of the following leaves headed by the same dividing marginal portion  24   a , his/her desired information is retrievable. The required information will be retrieved in printed mater  28  following the commencement arrow and continuing up to the terminating arrow. An intermediary indicia between the above arrows indicates the continuation of the relevant printed matter  28 . 
     In another embodiment of the present invention, depicted in FIG. 6, a booklet with indexing system, shown as  60 , is presented in an open position. Booklet  60  comprises several left and right leaves  12  and  14 , respectively, attached to a cover formed from left cover  34  and right cover  36 . 
     The lower part of left leaf  12  adjacent to front cover  34  so terminates that it is the shortest with respect to left leaves  12  overlying it, there being with each such subsequent leaf an increment in length, each increment being equal to the height of a marginal portion  24 . When booklet  60  is in an open position, each left leaf  12  is provided, above its marginal portion  24 , with a rectangular cut  55 , extending inwardly from side edge  20  and upwardly from this marginal portion  24  proximate lower edge  18 , to reveal a portion of each marginal portion  24 , located beneath it. Above marginal portion  24 , there is one or more duplicate marginal portions  24   b  corresponding to marginal portions  24  of each underlying leaf  12 . Thereby, the reader can identify from duplicate marginal portions  24   b  the content of each of the underlying leaves. He/she can then choose the desired content and turn the one or more leaves  12  to expose it. 
     All right leaves  14  overlie with their upper part the same upper part of back cover  36 . The lower part of right leaf  14  adjacent to back cover  36  is the longest with respect to right leaves  14  overlying it. 
     Each right leaf when overlying back cover  36  has above its marginal portion  24  the marginal portions of all right leaves  14  disposed on it. Thus, the required subject matter can be identified and then examined. When booklet  60  is in an open position, marginal portion  24  of left leaf  12  which is on the top refers to the same subject matter as does marginal portion  24  of right leaf  14  which is on the top. The offset between a left leaf  12  and its associated right leaf  14  when booklet  60  is open is equal to the height of one marginal portion  24 . 
     The information on indicia marking zone  26  and in the associated printed matter  28  is identically oriented for easy reading. 
     In another embodiment, depicted in FIG. 7, a booklet with an index system, shown as  70 , is presented in an open position. Booklet  70  comprises several left and right leaves  12  and  14 , respectively, attached to a cover formed from left cover  34  and right cover  36 . Left cover  34  has as an extension a foldable flap  64 . Right cover  36  has also, as an extension, a foldable flap  64 ′. All left and right leaves  12  and  14 , respectively, are provided with corner cuts  66 . Each left leaf  12  is provided at its upper and lower parts with a corner cut  66  except first left leaf  12  adjacent to front cover  34  which is provided only with a corner cut  66  at its lower part. 
     Each left leaf  12  has a corner cut  66 , between side edge  20  and upper edge  16 , which corner cut  66  extends inwardly and downwardly, delimited by a lateral side  68  parallel to side edge  20  and an internal side  70 . Internal side  70  can be either perpendicular to lateral side  68  or slanted to it. Each pair of successive left leaves  12  is provided with two corner cuts  66 , one having an internal side  70  which is perpendicular to lateral side  68 , another an internal side  70  which is slanted. This arrangement allows the use of indicia, for example numbers, as follows: when internal side  70  is slanted, an indicator such as a numeral is located near lateral side  68 , while when internal side  70  is perpendicular to lateral side  68 , the numeral is placed near side edge  20 . The above alternating locations for numbers allows double use of the available space for indexing, thereby leaving more space for printed matter  28 . Left leaves  12 , when turned and placed on right cover  34  (open booklet), become right leaves  14  also displaying corner cuts  66  at their lower part, proximate the intersection of side edge  20 ′ and lower edge  18 ′. Right leaves  14 , when booklet is open, are placed on back cover  36  and are provided at the bottom with corner cuts  66 , whose numbers are visible and form a sequence with those displayed on left leaves  12  at their top corner cuts  66 . Thus, all the information about the subject matter of booklet  70  is indexed and displayed and can be retrieved accordingly. Right leaves  14 , when turned and placed on left cover  34  (open booklet), become left leaves  12  which display corner cuts  66 , at their upper parts, at the intersection of upper edge  16  and side edge  20 . 
     The printed numbers associated with corner cuts  66  and the corresponding printed matter  28  are identically oriented for easy reading. 
     On foldable flap  64 , which extends from front cover  34 , there are rows  74  containing an identifying number, corresponding to the identifying numbers in the corner cuts  66 , each row  74  being accompanied by a brief description of a specific retrievable subject matter. Each row  74  is also identified by its specific background color. Additionally to the above, on said foldable flap  64 ′, one or more supplemental identifying numbers are displayed on a same row  74 , indicating the location of additional information related to the topic indicated by the identifying number of said row  74 . For example, additional information about topic  7 , found in printed matter  28 , will be designated by number  7  and highlighted to indicate its location and extent. Foldable flap  64 ′ which extends from back cover  36  is identical with foldable flap  64 ; alternatively, the information displayed on foldable flaps  64  and  64 ′ can be displayed on front cover  34 . 
     In a variant  80  (see FIG. 8) of the above embodiment  70 , use is made of left and right leaves  12  and  14  and front and back covers  34  and  36 , but without foldable flaps  64  and/or  64 ′. The assembly thus formed constitutes a basic unit wherein a common cover  76 , formed from a plurality of front and back covers  34  and  36  is used. 
     A succession of non-overlapping basic units are connected to both sides alternatively of a common cover  76  formed by a succession of front and back covers  34  and  36 . Optionally, this variant includes at one or both ends of common cover  76  a foldable flap  64  ( 64 ′) (not shown in FIG. 8) but described in the above embodiment. The information provided by foldable flap  64  is associated with the information exposed in the adjacent left and right leaves  12  and  14 , attached on the same side of common cover  76 . 
     In another simplified embodiment  90  shown in FIG. 9, there is shown an entity  78  having two parallel spaced leaves  12  or  14  integrally formed from one sheet of material. Each of leaves  12  or  14  has its own pivoting line. 
     In another simplified embodiment  100 , shown in FIG. 10, a cover formed from a front cover  34  and a back cover  36  shares its folding line  32  with that of pivoting line wherein a leaf  12  or  14  is attached to said entity  78 . 
     In another simplified embodiment  110 , shown in FIG. 11, an entity  78  is attached with one its pivoting lines to folding lines  32  between a front cover  34  and a back cover  36 . In another simplified embodiment  120 , shown in FIG. 12, use is made of a cover formed from a front cover  34  and a back cover  36  joined at a folding line  32 . The latter coincides with one of the pivoting lines of a first entity  78  attached to back cover  36 . A second entity  78  is laterally spaced and attached in parallel also to back cover  36 . 
     In yet another embodiment, depicted in FIG. 13, an indexing system, shown as  130 , is presented. Indexing system  130  comprises a plurality of left and right leaves  12  and  14  and a cover formed from a front cover and a back cover  36 . In the present embodiment, front cover  34  is provided with foldable flap  64 . Alternatively, back cover  36  can be provided with foldable flap  64 ′. Optionally, no foldable flap  64  is used, in which case the contents of foldable flap  64  is displayed on the internal face of front cover  34 . 
     Each left leaf  12  when it is superposed on front cover  34  has printed matter  28  on its front face  43 . Each left leaf  12  is also provided along the upper part of its front face  43  with an indicia marking zone  26 . When any left leaf  12  is superposed on back cover  36 , it becomes a right leaf  14 . When all left leaves  12  are superposed on back cover  36 , a portion of marginal portion  24  of each right leaf  14  is revealed by use of sequential corner cuts  66 . 
     Each first right leaf  14  of a group of sequential leaves has a corner cut  66  which reveals indicia or markings of each of the other right leaves  14  belonging to the same group. The area of corner cuts  66  of subsequent right leaves  14  starting from the topmost right leaf, which indicates the group, diminishes in a step wise fashion. Thus, each corner cut  66  is so formed so as to show its own indicia and at the same time allow indicia or markings of all subsequent leaves  14  to be exposed. 
     Each group of right leaves  14  is basically characterized by having the same distance between inside edge  22 ′ and side edge  20 ′. When two groups of right leaves  14  are superposed on back cover  36 , they are so dimensioned that the above distance in the top group is shorter than that of the second group, thereby revealing marginal portion  24  of the underlying group, together with corner cuts  66 . 
     Foldable flap  64  is provided with a plurality of rows  74 . In the present case, in a first row  74 , a capital letter indicates the group. The following rows  74 , sequentially by numbers, indicate the subgroups which constitute the two groups. Each number is accompanied by a brief description of the associated printed matter  28 . Optionally, each capital letter identifying a group is also accompanied by a definition of the group. Rows  74  in their entirety provide a summary of the contents of indexing system  130 . Conveniently, each letter which characterizes a group is associated with a background color, while each number which identifies a subgroup has its own background color. Optionally, the same background color is used for the same number in both groups. 
     Printed matter  28  and its associated indicia markings are identically oriented for easy reading. 
     In another embodiment shown diagrammatically in FIG. 14 as  140 , use is made of two entities  78  which are superposed and then located within a third entity  78 , the latter being also located within a fourth entity  78 . In this embodiment, two entities  78  which are adjacent have their adjacent leaves sharing a common pivoting axis. In this embodiment, the entities  78  which form an assembly of three superposed entities  78  are so disposed that the distance between two parallel leaves of the uppermost entity is reproduced in the distance between any successive leaves of said entities. Fourth entity  78  within which the assembly of three superposed entities is located is so disposed that there are adjacent leaves of the third and fourth entities which share a common first axis. 
     In another embodiment shown diagrammatically in FIG. 15 as  150 , use is made of two laterally spaced assemblies of entities  78 . Each assembly of entities  78  is constructed of two superposed entities  78 , equally spaced. Two assemblies of entities  78  are disposed within a third entity  78 . Adjacent leaves of third entity  78  and entity  78  which overlies it share a common pivoting axis. 
     In another embodiment  160  (shown diagrammatically in FIG.  16 ), two assemblies of entities  78 , each formed of two entities  78 , superposed between themselves, are laterally spaced and located within a third entity  78 . An arrangement of spaced-apart two third entities  78  is located within a fourth entity  78 . Adjacent leaves of fourth entity  78  and entity  78  overlying it share a common pivoting axis. 
     In another embodiment  170 , shown diagrammatically in FIG. 17, use is made of a plurality of entities  78  superposed within each other so that adjacent leaves of adjacent entities share a substantially common pivoting axis and so form two spaced sets of leaves. 
     In another embodiment  180 , shown diagrammatically in FIG. 18, use is made of a plurality of superposed entities  78  wherein adjacent leaves of adjacent entities share a common axis of pivoting. The above plurality is disposed within another such plurality of a larger size. 
     In another embodiment of the present invention, depicted in FIG. 19, an indexing system shown as  190  is presented in an open position. A plurality of first entities  78  superposed within each other results in two sets of leaves, a left set of leaves  84  and a right set of leaves  86 . Each set  84  ( 86 ) is constituted of leaves  12  ( 14 ) adjacent to each other. Each set  84  ( 86 ) of leaves  12  ( 14 ) shares a substantially common pivoting axis  88  or  88 ′. 
     Common pivoting axis  88  of left set  84  is appended on back cover  36  substantially adjacent folding line  32  between front and back covers  34  and  36 . Common pivoting axis  88 ′ of right set  86  is offset with respect to common pivoting axis  88  and appended on back cover  36  as well. It is obvious that the surface of each entity  78  between the two common pivoting axes  88  and  88 ′ is also appended to back cover  36 , directly or indirectly by appending successively to the respective underlying surface. 
     The plurality of entities  78  appended as described above is followed laterally by another plurality of first entities  78 , which is also appended to back cover  36 . The distance between the two pluralities of entities  78  equals the distance between common pivoting axis  88  and  88 ′. When all leaves  12  ( 14 ′) belonging to the two pluralities of entities  78 —each of the two pluralities of entities  78  having its two sets  84  and  86 —are completely turned to overlie back cover  36 , the following disposition can be seen: due to the distance between the axis of left and right sets  84  and  86 , respectively, and also due to the distance between the two successive pluralities of entities  78 , each succeeding set  84  ( 86 ) extends outwardly with respect to the preceding by an increment equal to the distance between the two common pivoting axes ( 88  and  88 ′) of the left and right sets  84  ( 86 ). Thus, an exposed lateral marginal portion  24  is formed. 
     Each leaf  12  ( 14 ) of a set  84  ( 86 ), except the last leaf of a set  84  ( 86 ) is provided with a stepped corner cut  92 , characterized by a top edge  94  and a lateral edge  96 . Each succeeding leaf  12  ( 14 ), when the indexing system is open and all leaves  12  ( 14 ) are superposed on back cover  36 , has its stepped corner cut  92  reduced with respect to the preceding leaf by an extension downwardly of top edge  94 . The size of this extension is chosen so as to expose a surface for displaying indicia. The inward extension of stepped corner cuts  92  of each set  84  ( 86 ′) is commensurate with the outward extension of exposed lateral portion  24 . Impliedly, each successive set  84  ( 86 ) will display its stepped corner cuts  92  together with the exposed marginal portion  24 . First leaf  14  of a right set  86  has a corresponding surface for displaying indicia, situated above top edge  94 , which surface does not form an extension. 
     A foldable flap  64  which extends from front cover  34  is used. The printed matter  28  and indicia on indicia marking zone  26  are identically oriented for easy reading. 
     When indexing system  190  is in an open position, on the top of front face  43  of uppermost leaf  12  exposed to the reader, besides printed matter  28 , there is a numerical marking followed by an arrow. The arrow indicates the commencement of the text of printed matter  28 , which text usually continues on the associated front face  44  of a leaf  14  turned completely on back cover  36 . After the numerical marking and the arrow there is a brief description of printed matter  28  disposed on faces  43  and  44 , respectively. Beneath the above information constituted of a numerical indicator and arrow and a brief description, use is made of a capital letter indicating the group to which leaf  12  with its front face  43  belongs. 
     When two left sets  84  are superposed on front cover  34 , the one closest to cover  34  extends outwardly with respect to the overlying one, thereby exposing its marginal portion  24 . On exposed marginal portion  24  a capital letter indicating which left set superposed on this exposed marginal portion  24  and having its front face  43  exposed, follows. If the open left set  84  is the first one starting from front cover  34 , the above capital letter will be represented on the front cover  34  on a zone equivalent to exposed marginal portion  24 . 
     On front face  44 ′ belonging to right set  86 , beside printed matter  28 , there is a capital letter indicating the group and a numerical indicator marking the corresponding front face  44 , both preceded by an arrow indicating the termination of printed matter  28 . The same pattern is followed by next plurality of entities  78 . 
     On foldable flap  64  there is a series of rows  74 , disposed horizontally in sequence. A group is designated by a column  74  indicating, by a capital letter, the associated subgroups disposed in rows  74  with numbers in sequential order, each designating the subgroup of information exposed on corresponding front faces  43  and  44 . Background colors are assigned to distinguish groups and subgroups. 
     In another embodiment of the present invention, depicted in FIG. 20, an indexing system, shown as  200 , is presented in an open position. Two pluralities of entities  78  are used. The pluralities of entities  78  which are superposed within each other are also divided in two sets, a left  84  and a right  86 . Each set  84  ( 86 ) is constituted of leaves  12  ( 14 ) adjacent to each other and each set  84  ( 86 ) of superposed leaves  12  ( 14 ) shares a substantially common pivoting axis  88  or  88 ′. Each pair of leaves  12  ( 14 ) constitutes an entity formed from a single sheet of material. 
     A first plurality of entities  78  has its common pivoting axes  88  and  88 ′ appended to front cover  34 , proximate to folding line  32  of the latter. A second plurality of entities  78  has its common pivoting axes  88  and  88 ′ appended to back cover  36 , also proximate to folding line  32 . 
     The relative position of the two pluralities of entities  78  is such that, when the two pluralities of entities  78  are rotated completely to overlie front or back cover  34  or  36 , marginal portion  24  is so formed to be equal to exposed marginal portions of a succeeding or preceding group. 
     All subsequent leaves  12  ( 14 ) of the two pluralities of entities  78  are basically made from identical sheets. 
     In the open position of booklet  200 , there are several leaves  12  overlying front cover  34  and several leaves  14  overlying back cover  36 . In the former named leaves, each pair of aligned leaves  102  is overlain by another pair of aligned leaves  12 , the latter being offset downwardly with respect to the previous pair, starting from the upper part of front cover  34 . In each pair of leaves  12 , the second or underlying leaf  12  is provided with a jogged corner cut  98  wherein part of its upper edge  16  is situated downwardly with respect to upper edge  16  of the previous leaf  12  of the same pair. When the same leaves  12  are rotated now completely to the right to overlie the ones  14  already-disposed, they also become right leaves  14 . Each leaf  14  has its jogged corner cut  98  so formed so as to expose an indicia marking zone of a preceding leaf  14 . 
     Thus, each first leaf  14  of a pair has its upper edge  16  aligned with jogged corner cut  98  at the bottom of the latter. Each pair of leaves  14 , starting with the pair adjacent to back cover  36 , is followed by another pair of leaves  14 , offset upwardly respect to the previous pair, starting with the paid adjacent to back cover  36  In each pair of leaves  14 , the top one is provided with a jogged corner cut  98 . In each jogged corner cut  98 , part of its lower edge  18 ′, which starts from side edge  20 ′, is situated upwardly with respect to the lower shared edge  18 ′. The height of jogged corner cut  98  so formed is also chosen to expose an indicia marking zone of the underlying leaf  14  of the pair. 
     The first leaf  14  of a set  86  when completely turned to the right to overlie back cover  36  has its lower edge  18 ′ upwardly displaced so as to expose all the marginal portions with indicia of the entire set. The first leaf  12  of a set  84  when set  84  is turned to the left, so as to overlie front cover  34  has its upper edge  16  downwardly displaced so as to expose all the marginal portions of leaves  12  of the same set  84 . 
     Index system  200  is used as follows: in its open position, when all leaves  14  are turned to the right to overlie back cover  36 , one can see on front cover  34  a series of rows  74  which are horizontally disposed in sequence. All groups and subgroups of information contained in booklet  200  are displayed. Each group is indicated by a capital letter. Since each group has its several subgroups, each row  74  defining a group is characterized by several rows  74 , in which the specific subgroup is indicated by a numerical marking. Each row  74 , beside the indicia marking a group or subgroup, contains a brief description summarizing corresponding subject matter contained in associated printed matter  28 . To distinguish groups and subgroups, background distinctive colors are used. Optionally, the information displayed on front cover  34 , as described above, is displayed on a foldable flap  64 . 
     As stated before, each so-formed pair has one leaf  12  closer to front cover  34  and another one on top of it, closer to the reader. On each marginal portion of each leaf  12 , close to its side edge  20 , there are markings indicating the group and subgroup to which respective front face  43  belongs. 
     When two sets  84  are superposed on front cover  34 , the preceding unit  84 , closer to front cover  34 , being outwardly extended, will reveal information displayed on the last face  43  of the previous set  84 . This information indicates the group to which the underlying pages belong. 
     Again, when the indexing system  200  is open, one can see on leaves  14  overlying back cover  36 , with their jogged corner cuts  98  disposed near lower edge  18 ′, the same type of indicia markings as described above (when jogged corner cuts  98  are described in connection with leaves  102  completely rotated to the left). 
     In another embodiment of the present invention, depicted in FIG. 21, an indexing system in a notepad form is shown as  210  in an open position. A cover is formed by front cover  34  and back cover  36  between which folding line  32  is used. There are several entities  78  which are superposed on each other. Each entity  78  forms a left set  84  and a right set, appended together to back cover  36 . Common pivoting axes  88  ( 88 ′) shared by left and right sets  84  ( 86 ), respectively, are disposed perpendicularly to folding line  32 . 
     The first set of entities  78  has its common pivoting axis  88  substantially proximate to upper edge  16 ′ of back cover  36 . The distance between two pluralities of entities  78  is substantially equal to the distance between common pivoting axes  88  and  88 ′ of the same plurality of entities  78 . 
     When indexing system  210  is in an open position and all subsequent leaves  14  of the two successive pluralities of entities  78  are fully rotated to overlie back cover  36 , one can see the following: due to the distance between common pivoting axes  88  and  88 ′ of left and right sets  84  and  86  of a plurality of entities  78  and the distance between two successive pluralities of entities  78 , a portion of all preceding left and right sets  84  and  86  opposite to common pivoting axes  88  ( 88 ′) is always exposed. Also, when all leaves  14  of both pluralities of entities  78  are turned completely on back cover  36 , one can see that each set  84  ( 86 ) has its corner remote from folding line  32  and common pivoting line  88  ( 88 ′) provided with an exposing cut. 
     Each exposing cut  102  is identified by an uppermost edge  104 . In each set  88  ( 88 ′), each subsequent uppermost edge  104  of an exposing cut  102  extends downwardly with respect to the previous one of an underlying front face  44  of a leaf  114 . Thus, all succeeding front faces  44  of a set  86  can be identified. 
     On a front cover  34  a plurality of rows  74  are horizontally disposed in sequence. Several succeeding rows  74  of the same set  84  ( 86 ) are preceded by a capital letter indicating a specific group. Each row  74  has its number which indicates a subgroup of the specific group. Following the number there is a brief description of the content of each subgroup. In the same row  74 , following the numeral and the brief description, when it is case, reference about the same subject in another group and subgroup is marked by a capital letter followed by a number. 
     Each leaf  14  when it is pivoted away from back cover  36 , thus becoming a left leaf  12 , reveals on its upper corner, opposite to its exposing cut  102 , a marking. This marking contains a capital letter followed by a number and a commencement arrow. Thus, the printed matter  28  on front face  43  containing the above marking is identified. 
     When booklet  210  is open, front face  44  of the leaf  14  of an overlying set  86 , when rotated completely onto back cover  36 , reveals on its marginal exposed portion a capital letter and a succession of brief descriptions for the group and its subgroups, aligned with corresponding indicia designating a subgroup. 
     The following leaves  14  have their termination marking above the uppermost edges of their exposing cuts  102 . These markings contain a terminating arrow followed by a capital letter for the specific group and a number indicating the subgroup. 
     Each printed matter  28 , if it is the case, contains additional subject matter referenced from front cover  34 . This additional subject matter is referenced beside brief descriptions of sub-groups in rows on the front cover. 
     In order to distinguish groups and subgroups, background colors are used. 
     The printed information on indicia marking zone  26  and in the text of printed matter  28  is identically oriented throughout the booklet for easy reading. 
     In a further embodiment, depicted in FIG. 22, shows in open position an indexing system  220  in notepad form, so oriented, in notepad form, that the leaves are turned towards and away from the reader when the booklet is in use. A cover is formed by a front cover  34  and a back cover  36 , between which folding line  32  is used. There are three pluralities of entities  78 . In each plurality, entities  78  are superposed within each other. A plurality formed as two sets, a left and a right  84  and  86  respectively. All three pluralities of entities  78  are appended to back cover  36 . 
     In all three pluralities of entities  78 , common pivoting axes  88  ( 88 ′), shared by left and right sets  84  and  86 , respectively, are disposed perpendicularly to folding line  32 . The first of the three pluralities of entities  78  has its common pivoting line  88  substantially proximate to upper edge  16 ′ of back cover  36 . The distance between first, second and third pluralities of entities  78  is substantially equal to the distance between common pivoting axis  88  and  88 ′ of the same plurality of entities  78 . d 
     When indexing system  220  is in open position and all leaves  14  of the three pluralities of entities  78  are fully rotated to overlie back cover  36 , one can see: due to the distance between common pivoting axes  88  and  88 ′ of left and right sets  84  and  86  of plurality of entities  78  and also due to the distance between each successive plurality of entities  78 , a portion of all preceding left and right sets  84  and  86 , opposite to common pivoting axis  88  ( 88 ′), is also exposed. When indexing system  220  is opened and all leaves  14  and  16  are turned away from back cover  36  and become left leaves  12 , due to the above distances between the common pivoting axes of two successive sets and the distance between each of pluralities of entities  78 , a marginal portion of all sets is exposed. Also, when leaves  12  of all three pluralities of entities  78  are turned completely on back cover  36 , and become right leaves  14 , one can see the following: each set  84  ( 86 ) comprises three successive leaves  14 ; the uppermost leaf  14  being provided with a laterally extended cut  106  through which the underlying indicia marking zones of the remaining two leaves  14  arc exposed. The following leaf  14  is also provided with a laterally extending cut  106  to expose the underlying leaf  12 , wherein no laterally extended cut  106  is provided. Each laterally extended cut  106  has a lateral edge  108  parallel to folding line  32 . 
     Leaves  14  underlying the first and uppermost leaf  14  has its lateral edge  108  outwardly displaced with respect to the one of the first and uppermost leaf  14 . The displaced extension is used for indicia. Obviously, the same pattern is repeated for all subsequent sets  84  ( 86 ). When the leaves  14  are rotated away from back cover  36 , thus becoming left leaves  12 , one can see the following: each left or right set  84  ( 86 ) has three leaves  12  ( 14 ). In order to expose to the reader the indicia markings of the three leaves  12 , successively superposed, the one closest to the reader is provided on one of its lateral edges  108  with a rectangular cut  55  exposing indicia markings of the two subsequent leaves  12  of set  84 . Leaf  12  under the one closest to the reader is also provided with a rectangular cut  55  of a reduced size. 
     Rectangular cut  55  with reduced size has a lower edge  110  which extends outwardly from a common pivoting axis  88 ′. The extension is so dimensioned that it provides space for exposing indicia. 
     On front cover  34  there is a series of rows  74  which are horizontally disposed in sequence. A column disposed close to the edge of the front cover  34  contains a sequence of capital letters indicating groups. To each capital letter correspond several rows  74  indicating subgroups associated with the group designated by the capital letter. Each subgroup is identified by a numerical marking followed by a brief description of the content of the subgroup. When left and right units  84  and  86  are turned to overlie back cover  36 , one can see the following: on the visible associated front faces exposed to the reader, there is, where necessary, a capital letter followed by a commencement arrow and a capital letter preceded by a termination arrow. In the event that use is made of only one face to present the information, both of the arrows (commencement and termination) are found on the same face, with the accompanying letters and numerals being disposed on the same face at its beginning and end. 
     When leaves  14  are turned away from back cover  36 , thus becoming left leaves  12 , on the upper portion on each last leaf  12  which is closest to the reader, one can see the capital letter indicating the group and characterizing its subgroups underneath. The same pattern follows for the remaining sets  84  ( 86 ). Since use is made of rectangular cuts  55  only for the two upper leaves  12  of a set  84 , under each lower lateral edge  110 , there is a numeral identifying a subgroup. The last leaf  12 , furthest from the reader and not provided with a rectangular cut at  55 , has numerical markings visible through the corresponding rectangular cuts  55  in the overlying leaves  12 . 
     When leaves  12  are rotated to overlie back covers  36 , thus becoming right leaves  14 , at the bottom of each exposed leaf  14 , there is a marginal portion which ends with a numerical marking. The first leaf  14  of a set closest to the reader, besides the numerical marking of the subgroup, comprises a capital letter for the group and a brief description of the contents of the group. 
     Background colors, for distinguishing the groups among themselves, are used together with the corresponding capital letter. Each numerical marking of a subgroup has a chosen color associated with it which repeats when the same number is reused as a subgroup identifier in another group. Printed matter  28  and indicia disposed on indicia marking zones  26  are identically oriented for easy reading. 
     In another embodiment (FIG.  23 ), a multiply-folded single strip of material is shown as  230 . A series of successive entities  78  constitute the multiply-folded strip. Each entity  78  is connected to a next one by a folding line. A last entity  78  is followed by a leaf which is continued by a folded extension forming front and back covers. An exposing means results from spaced folds on the single strip. Said folding lines are cut so that the series of entities  78  becomes independent and their leaves  12  ( 14 ) are able to rotate. Webs that interconnect the leaves of each entities are attached to the front or back cover, at a distance equal to the distance between two leaves of an entity. In order to easily separate the entities, the folding lines defining their top edges are provide a guide for severing by means known in the field. Lengthwise, each leaf of each entity is divided in two and separated by a long slit to form two spaced groups of entities. 
     In another embodiment (FIG.  24 ), a multiply-folded single strip severed of material is shown as  240 . A series of successive and opposed entities  78  are made from one strip of material. Each entity is made from two parallel leaves, connected by a web. A last entity of the series of successive and opposing entities is followed by a folded extension, constituting a back and a front cover. To produce an indexing system, those webs remote from said folded extension are cut to separate the entities while the webs adjacent to the folded extensions are appended to respectively to the back or front cover. Longitudinally, the succession of entities is separated by a slit and folded around a middle axis of the folded extension. Thus two groups of successive entities can be attached and folded to the folded extension.