WHAT IS MAINFRAME ?
Mainframe is a High performance Multi User computer system which is the most scalable, available, reliable and secured machine in the world capable of performing some Million Instructions per second (upto 569,632 MIPS) with the following characteristics:
1) Reliable single-thread performance, which is essential for reasonable operations against a database.
2) Maximum I/O connectivity, which means mainframes excel at providing for huge disk farms.
3) Maximum I/O bandwidth, so connections between drives and processors have few choke-points.
4) Reliability--mainframes often allow for "graceful degradation" and service while the system is running.
Applications of mainframe various from computing the Random number series to census, industry and consumer statistics, ERP and financial transaction processing..