mainframe

Large computer used for commercial data processing and other large-scale operations. Because of the general increase in computing power, the differences between the mainframe, supercomputer, minicomputer, and microcomputer (personal computer) are becoming less marked.

Mainframe manufacturers include IBM, Amdahl, Fujitsu, and Hitachi. Typical mainframes have from 128 MB to 4 GB of memory and hundreds of gigabytes of disk storage. Their primary use is to conduct very fast transactions with a database and to be split into several independent partitions, each with its own operating system. A typical mainframe from IBM weighs between 1 and 2 tons.