Usually one at a time unless you are talking servers.
no
Very many people.
People who use the computer are often simply known as "users".
Advanced Computer users.
it allows many users
That is impossible to answer. As of 2012 Apple has about 15% of the computer market share.
All 10
a. About 200b. About 5000 users
250 users can work in mini computer at a time
Time sharing system allows many users to share the computer simultaneously. It is used when several users are linked through communication networks to a single computer.
Brain computer interfaces allow computer users to communicate and run computer commands using specialized computer equipment that is placed on the users head.
The People Who use The Computer. Therefore Them Being The Users :)