This invention relates generally to devices having keyboards, such as personal-digital-assistant (PDA) devices having soft keyboards as well as desktop and laptop computers having real, physical keyboards, and more particularly to determining in conjunction with such keyboards a most likely intended-to-be-typed keystroke or sequence of keystrokes. 
Small computerized devices that fit into the palm of one""s hand, generally referred to as personal-digital-assistant (PDA) devices, have become increasingly popular.  They allow users to look up and record information where computer access is inconvenient, such as when in one""s car, while shopping at the mall, during a business meeting, etc.  Unlike a typical desktop or laptop computer, which has an actual physical, or xe2x80x9creal,xe2x80x9d keyboard for text and data entry, a PDA device usually only has a small number of buttons, and a small touch-sensitive area on which a pen-like implement called a stylus can be used.  For text entry on such a device, the user is able to write letters or symbols corresponding to letters on the touch-sensitive area with the stylus, which the device attempts to recognize. 
However, for a variety of reasons, some users prefer not to input text into these devices in this manner.  Therefore, most PDA devices also permit a second form of text and data entry.  An image of a regular keyboard is displayed on the small display of a PDA device, such that a user is able to select which key to xe2x80x9ctypexe2x80x9d next by tapping the stylus on the part of the image of the keyboard corresponding to the desired key.  Such an image of a keyboard being displayed on the display of a device such as a PDA device, to provide for text and data entry on the part of the user by tapping the parts of the image corresponding to keys of the keyboard, is known as a xe2x80x9csoftxe2x80x9d keyboard. 
A disadvantage with such soft keyboards is, however, that the displayed keys of the keyboard on the display of the PDA device are very small, since the display of the device as well as the device itself are small.  This means that users are apt to tap incorrect keys, especially when xe2x80x9ctypingxe2x80x9d quickly, and also that users are apt to type more slowly using soft keyboards, because of the dexterity required in order to achieve a high accuracy rate when typing.  This limits the usefulness of these PDA devices, since they cannot very conveniently be used for quick and/or large amounts of text and data entry.  For this and other reasons, there is a need for the present invention. 
The invention relates to fuzzy keyboards, to determine a most likely intended-to-be-typed keystroke or keystrokes.  In one embodiment, a computer-implemented method adds each of one or more keys to each of a current list of key sequence xe2x80x9chypotheses,xe2x80x9d to create a new list of key sequence hypotheses, upon a key press event.  For a soft keyboard, for example, a key press event may be the actuation of a location within the soft keyboard rendered on a touch-sensitive display.  For a hard keyboard, for example, a key press event may be the actuation of an actual key on the keyboard.  The method determines a likelihood probability for each hypothesis in the new list, and then removes any hypothesis that fails to satisfy any of one or more thresholds.  In one embodiment, the most likely key sequence of the new list is displayed. 
In another embodiment specifically relating to soft keyboards, a computerized system includes a touch-sensitive display, a soft keyboard rendered thereon, and a computer program.  The computer program detects actuation of a location on the soft keyboard, and based at least thereon determines a most likely intended-to-be-typed key on the soft keyboard.  In another embodiment specifically relating to hard keyboards, a computerized system includes a keyboard and a computer program.  The computer program detects actuation of a key on the keyboard, and determines a most likely intended-to-be-typed key of the keyboard, based on at least the key actuated and either a key sequence of keys already determined to have been typed, a list of key sequence hypotheses, or both. 
Embodiments of the invention provide for advantages not found within the prior art.  With respect to hard keyboards, the user may be typing fast, for example, and press the xe2x80x9cdxe2x80x9d key instead of the xe2x80x9cexe2x80x9d key.  However, the most likely key sequence hypothesis may be such that the typing of the xe2x80x9cexe2x80x9d key is much more probable than the typing of the xe2x80x9cdxe2x80x9d key.  As an example, the user may have initially typed xe2x80x9cThxe2x80x9d prior to the xe2x80x9cdxe2x80x9d key.  Because the xe2x80x9cdxe2x80x9d key is close to the xe2x80x9cexe2x80x9d key, and few words begin xe2x80x9cThdxe2x80x9d while many words begin xe2x80x9cThe,xe2x80x9d and also because the user was typing fast, the key sequence xe2x80x9cThexe2x80x9d may be displayed instead of xe2x80x9cThd.xe2x80x9d
With respect to soft keyboards, keys that are determined as more likely to be entered by the user have a greater probability that they are intended to be typed when the user actuates a location close to those keys.  For example, if the user actuates the soft keyboard in the vicinity between the xe2x80x9cdxe2x80x9d and the xe2x80x9cfxe2x80x9d keys, and the most likely key sequence hypothesis is such that the xe2x80x9cdxe2x80x9d key is more likely than the xe2x80x9cfxe2x80x9d key to have been typed by the user, then the xe2x80x9cdxe2x80x9d key may be displayed.  In some embodiments of the invention, past keystrokes may also be changed, up to a predetermined number of keystrokes before the current keystroke. 
Furthermore, it is noted that in one embodiment of the invention, the fuzzy keyboard as described herein can be implemented in conjunction with the predictive keyboard described in the copending, coassigned, and cofiled application entitled xe2x80x9cPredictive Keyboardxe2x80x9d having U.S. patent application Ser.  No.  09/484,079.  However, the invention itself is not so limited. 
The invention includes computer-implemented methods, machine-readable media, computerized devices, computerized systems, and computers of varying scopes.  Other aspects, embodiments and advantages of the invention, beyond those described here, will become apparent by reading the detailed description and with reference to the drawings.