This monstrosity of a keyboard types entire words instead of individual letters, boasting a staggering 1,020 keys – and yes, it's just as impractical as it sounds. Inspired by Randall Munroe's ...

They usually help to combine keys or enable an elevated extra key marked on the keyboard. If you have seen extra keys marked on a key, i.e., in the image you can see there is a dot, hyphen ...