A mainframe is an ultra high-performance computer made of high-volume, to provide processor-intensive computing. They are typically used for large businesses and scientific purposes. This is why you will not see a mainframe in anyone’s house.
If we look at the hierarchy of computers , then the position of mainframes falls just below the supercomputers , which is one of the most powerful computers in the world (this is why they are called “supercomputers”. The mainframe can easily execute many programs simultaneously at a very high speed, but supercomputers are designed to do a single process. In the present time the biggest manufacturers of making mainframes include IBM and Unisys.