Until recently, keyboards and mice have used very little of our sensory and motor abilities. The Magic Trackpad 2 is a step in the right direction.
accessibility
The mother of all virtual keyboards, completely customisable, and operated by the input device of your choice.
A thorough account of Dictation in El Capitan, and how you can use your Mac despite having RSI, etc.
This can read webpages to you, provides support for Braille output devices, and has very extensive controls and customisation.
Many of us visual, hearing, and/or control issues with our Macs. Here is a guided exploration of the Accessibility pane and what it has to offer us.
Suddenly my Mac mini has started flashing the display instead of sounding an alert. How can I fix that?
Why does the cursor all but vanish in certain apps?
Google wants me to let its updater use accessibility features. Should I agree or not?
Occasionally the display zooms to around 300%. How can I stop that from happening?
Should we be using the Comic Sans font to improve accessibility for the dyslexic?
The Eclectic Light Company 