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What is a Mainframe Computer?

Jude Burtler, Paul Zandbergen
  • Author
    Jude Burtler

    Jude Burtler has a Master’s degree in Financial Economics from the Illinois State University and a Bachelor’s degree in Economics from the University of Illinois at Chicago. He has over 3 years in teaching Economics and Finance.

  • Instructor
    Paul Zandbergen

    Paul is a GIS professor at Vancouver Island U, has a PhD from U of British Columbia, and has taught stats and programming for 15 years.

Learn the definition of mainframe computer and see how a mainframe system is used. See examples of mainframes, and compare mainframe vs. supercomputer. Updated: 05/06/2022

Table of Contents


What is a Mainframe Computer?

A mainframe computer is a large computer capable of rapidly processing massive amounts of data at high speeds. Mainframe computers by definition are computers that have a lot of memory and processors, so they can do billions of transactions and simple calculations in real time. A mainframe is used for transaction servers, commercial databases, and applications that need ample reliability, security, and speed.

By definition, a mainframe will process enormous volumes of data at a quick rate. Large-scale operations such as censuses, industry and consumer data, ERP, and other similar tools are essential for a wide range of different types of work. Major businesses rely on mainframe computers for key applications like bulk data and transaction processing.

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  • 0:01 Definition
  • 0:20 Development of Mainframes
  • 1:25 Mainframe Capabilities
  • 2:03 Present-Day Use of Mainframes
  • 3:50 Supercomputers & Servers
  • 5:00 Lesson Summary
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Development of Mainframe Computers

The first mainframe computer was invented in the 1930s by Harvard scholar Howard Aiken, who popularized the name mainframe. His idea was to build a massive calculator for the solution of a set of nonlinear equations. However, it wasn't until 1943 that the machine was ready for operation. It cost roughly $200,000 to create, weighed five tons, and took up a whole room. From the late 1950s through the early 1970s, a small number of manufacturers produced centralized server PCs. They were known as "IBM and the Seven Dwarfs," a group of manufacturers that included IBM as well as Honeywell, GE, NCR, Burroughs, Control Data, UNIVAC and RCA.

Mainframe computers are still physically large. In the 1940s, a mainframe was about the size of a one-car garage. However, over the course of the 1950s, mainframe computers decreased in size. A standard example of a mainframe computer would be roughly the height and width of a 6-foot-high closet. Mainframes have remained about this size. With current technology, it would be impossible to fit all of a mainframe's processing and memory into a substantially smaller desktop case.

Example of Mainframe Computer

Modern businesses employ mainframes for various purposes, including banking, insurance, healthcare, government and public utilities. Mainframes are regarded as the most stable, secure, and compatible of all computing platforms. The mainframe is accessed via the support element (SE), because it is the most straightforward method. For an IBM Z mainframe, the support element console serves as the central point of control (CPC) for all of its components. It is physically coupled to the central processing unit (CPU) and is housed within a CPC frame. The hardware management console (HMC) and the operating system on the mainframe are powerless in the face of this software. The IBM processor LAN is connected to the HMC cluster communication system and can be accessed from an IP business network, if it has been configured properly. Systems such as IBM zSeries, System z9, and the new System z10 are good examples of mainframe computers.

An example of a mainframe computer

z10 Enterprise-class mainframe computer system

Mainframe Operating System and Capabilities

What is a mainframe system? Essentially, a mainframe system is the core data repository, or hub, in a corporation's data processing centre, and it is connected to users through less capable devices such as workstations, terminals, and other similar devices. Mainframe operating systems are advanced technologies with a wide range of characteristics and objectives that differ significantly from one another. They are operating systems —a group of programs that manage the inner workings of a computer system, such as the storage devices and operating system of the memory, processors and peripherals— specifically for mainframe computers. Z is a super-stable operating system for mainframe computers that are used for essential applications. IBM introduced this operating system in 2000. It assures the security and maintenance of the computer. The architecture of Z is based on a 64-bit design. Mainframe computers still run the Z operating system. Compatibility and dependability are two of the mainframe computer's characteristics. Proper forethought and execution are needed to bring these features to life.

Present-Day Use of Mainframes

Most large businesses and organizations have at least one mainframe computer. Significant financial institutions, federal government agencies, and major aviation companies are likely to use a mainframe system. The purpose of a mainframe system is to handle large amounts of data. The acquisition and maintenance costs of a mainframe system are prohibitively high, and therefore its use is usually limited to large organizations. A mainframe is typically used by corporations that handle a large volume of transactions.

Why are mainframes necessary? While it is true that a typical modern desktop PC has greater computing capability than a mainframe computer from the 1980s, mainframes outperform PCs in high-volume transaction processing. When it comes to transactions, a desktop PC is able to process them, but a mainframe can handle a lot more data. In addition, a mainframe is more secure than a desktop PC because it is practically isolated in its own room. Mainframes are better able than PCs to rapidly process enormous volumes of data, such as in transaction processing.

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Frequently Asked Questions

What are examples of mainframe computers?

Examples of mainframe computers include the universal automatic computer from UNIVAC series and the ZSeries mainframe computer from IBM. Another example is a system named Non-Stop by the manufacturers of Hewlett Packard.

Why are mainframe computers used?

Most corporations opt to use mainframes particularly for applications that depend on reliability and scalability. For instance, financial institutions such as banks prefer to use mainframes to host their customer accounts database.

Are mainframe computers still used today?

Mainframes are still used in today's world. They play a significant role in the daily operations of many large corporations, particularly in the business environment with organizations such as financial companies and airlines.

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