Mainframes Computer

A mainframe computer is a very large computer capable of handling and processing very large amounts of data quickly. They are used by large institutions, such as government agencies and large corporations.

Definition

The term mainframe computer is used to distinguish very large computers used by institutions to serve multiple users from personal computers used by individuals. Mainframe computers are capable of handling and processing very large amounts of data very quickly - much more data than a typical individual needs to work with on his or her own computer.

Development of Mainframes

Mainframe computers were developed in the 1950s, have continued to evolve and are still in use today. Mainframe computers are designed to handle very high volumes of input and output and are optimized for computational speed. The speed of mainframes is expressed in million instructions per second (or MIPS). Before the development of powerful personal computers, many agencies relied heavily on mainframes for most of their computing needs. For example, this photograph shows one of the computer rooms at NASA back in 1962.

Mainframes acquired their name because of their size, typically as large as a six-foot-tall closet. They also required specialized heating, ventilation and cooling, as well as a dedicated power supply. In practice, this meant a separate room had to be dedicated to house the mainframe computer systems. One of the characteristics of early mainframes is that they did not have the typical interactive interface we are used to with personal computers. Early mainframes accepted all kinds of different inputs, and later versions typically had a dedicated terminal, similar to a modern display monitor with a keyboard.

Mainframe Capabilities

Mainframe systems can be used by a large number of users. This means that, in a large organization, individual employees can sit at their desk using a personal computer, but they can send requests to the mainframe computer for processing large amounts of data. A typical mainframe system can support hundreds of users at the same time. As for the actual hardware components inside a mainframe computer, they are similar in type to what personal computers use: motherboard, central processing unit and memory. The individual components are just a lot more powerful and a lot more expensive.

Present-Day Use of Mainframes

With the technological advances in personal computers, the need for mainframe computing has substantially reduced over the years. The computing power of a typical desktop computer today is greater than that of a mainframe system back in the 1980s. However, mainframe systems continue to be widely used for reliable transaction processing.

Consider all the transactions that a bank with 1,000 branches across the country needs to process every day. A single desktop computer wouldn't be able to handle this volume of transactions, and it also would not be very secure. So, somewhere in a room with no windows and restricted access sits a mainframe computer crunching all these transactions while creating multiple back-ups along the way for security purposes.

Now, think of different types of industries and their services: airline reservations, electronic commerce, inventory control, shipping, etc. They all need reliable and fast processing of transactions. Not all transaction processing needs to be conducted on mainframes, but it remains one of the market segments in which mainframe computing is very important.