An image forming apparatus comprising: a user interface unit that comprises a scan area operable to receive a scan object; an image reading unit that is operable to read an image of the scan object disposed on the scan area; a driving unit that is operable to move the image reading unit on the scan area; an operation performing unit that is operable to perform an operation by using the image read by the image reading unit; and a control unit that is operable to control the operation to be performed according to a position of the scan object on the scan area, wherein the scan area comprises a determination area and a function area, wherein the determination area extends from a first position of the image reading unit to a second position of the image reading unit on the scan area, and the function area extends from the second position of the image reading unit to a third position of the image reading unit on the scan area the control unit being operable to determine whether the scan object exists on the determination area and when it is determined that the scan object exists on the determination area, being operable to control the operation performing unit to store or print the read image, and when it is determined that the scan object does not exist on the determination area, being operable to perform a function which is preset according to a position of the scan object on the function area, wherein the control unit comprises: a position determining unit that is operable to determine a position of the scan object on the function area; and a function selecting unit that is operable to select a function corresponding to the determined position, wherein one or more reference positions (R1, R2, R3) of the image reading unit each corresponding to a predetermined function exist on the function area, wherein the function selecting unit is operable to determine whether the determined position of the scan object is located at any one of the one or more reference positions (R1, R2, R3) and selects a function corresponding to the one or more reference positions (R1, R2, R3). a user interface unit that comprises a scan area operable to receive a scan object; an image reading unit that is operable to read an image of the scan object disposed on the scan area; a driving unit that is operable to move the image reading unit on the scan area; an operation performing unit that is operable to perform an operation by using the image read by the image reading unit; and a control unit that is operable to control the operation to be performed according to a position of the scan object on the scan area, wherein the scan area comprises a determination area and a function area, wherein the determination area extends from a first position of the image reading unit to a second position of the image reading unit on the scan area, and the function area extends from the second position of the image reading unit to a third position of the image reading unit on the scan area the control unit being operable to determine whether the scan object exists on the determination area and when it is determined that the scan object exists on the determination area, being operable to control the operation performing unit to store or print the read image, and when it is determined that the scan object does not exist on the determination area, being operable to perform a function which is preset according to a position of the scan object on the function area, wherein the control unit comprises: a position determining unit that is operable to determine a position of the scan object on the function area; and a function selecting unit that is operable to select a function corresponding to the determined position, a position determining unit that is operable to determine a position of the scan object on the function area; and a function selecting unit that is operable to select a function corresponding to the determined position, wherein one or more reference positions (R1, R2, R3) of the image reading unit each corresponding to a predetermined function exist on the function area, wherein the function selecting unit is operable to determine whether the determined position of the scan object is located at any one of the one or more reference positions (R1, R2, R3) and selects a function corresponding to the one or more reference positions (R1, R2, R3).