He has lost the ability to use a keyboard altogether and can do very little with a pen. His most recent four books have been written entirely by dictation, and with the help of his assistant of 12 years, Rob Wilkins.
"I can no longer type, so I use TalkingPoint and Dragon Dictate," Pratchett says, as Rob drives us to the café in a rather unexpected large gold Jaguar. "It's a speech-to-text program," he explains, "and there's an add-on for talking which some guys came up with."
If you're a Terry Pratchett fan, you'll have tears in your eyes when you read the above interview.
HIs daughter Rhianna will continue the Discworld series when he's gone.