An On-Screen Keyboard (frequently abbreviated to OSK) is a visual representation of a standard keyboard that can be installed on any Windows computer.
Many users who struggle to use a keyboard are able to use a mouse, rollerball, joystick, headpointer or other pointing device. Many OSKs can be accessed by switches for those with more severe physical difficulties.
The flexibilityof their visual display combined with audio output makes some OSKs suitable for people with visual impairment as well as physical difficulties.
An On-Screen Keyboard needs to have many access options to be able to cope with a wide range of physical needs. Useful access features include:
As a general rule the more access features the software has the more expensive it will be. All OSKs provide the user access to the letters of the alphabet, numbers, some punctuation and other common keyboard keys. Other feature-rich keyboards offer the facility to make your own 'keys' that can perform much more advanced tasks such as launch a program or even operate environmental control.
Typing on an on-screen keyboard can be slow and some switch users in particular can only produce a few letters a minute. Prediction allows words to be completed automatically and can greatly increase the overall typing rate for slower users. Dasher's prediction is slightly different in that it works letter-by-letter rather than word-by-word.
You might also want to check out Chapter 7 of the CALL Centre's free ebook on Special Access Technology:
A basic OSK is bundled free with Windows XP and as such it is likely to be already installed on the computer you're currently using.
Windows XP's built-in On-Screen Keyboard can usually be found under:
Start > All Programs > Accessories > Accessibility > On Screen Keyboard
If you struggle to find it you can run it manually using the Run dialog:
Start > Run > type "OSK" > press ENTER
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