Some keyboards are displayed on the computer screen and represent a standard keyboard. The keys are pressed by pointing to the key with a mouse and clicking.
For users whose visual limitations are less severe, keyboards with larger keys are available.
Individuals with physical challenges often use computers, but sometimes they need special input devices to access them.
To aid users with motor control issues, special trackballs are available that are manipulated easily with one finger and are attachable to almost any surface.