Area where computers can be used?

Computers are, essential, machines for manipulating information. So anywhere there is information is, potentially, an area for using computers.

Pretty much everything we sense (light, sound, touch, smell, taste et cetera) and many things we can't sense - (eg radio, X-rays) can be described as information so there are a huge number of applications and it's quite difficult to think of areas of human activity that can't be affected by computers.