Mainframe computers are big massive computers that takes a lot of space. e.g. A room. Their main use is to save and process a huge amount of data in a small period of time. A mainframe can store up to MILLIONS of gigabytes where a normal pc can only store 1000 gigabytes.

 

Mainframes are mostly used in huge companies that need to store a large amount of information. such as a bank, a casino, a hotel and so on.