Learning Objectives

By the end of this chapter, you will be able to:

  • Classify computers based on their size and processing power.
  • Define and provide examples of microcomputers.
  • Differentiate between minicomputers, mainframes, and supercomputers.

Classifying Computers

Digital computers can be classified into several categories based on their physical size, processing power, and application. The four main classifications are microcomputers, minicomputers, mainframe computers, and supercomputers.

1. Microcomputers

Microcomputers are the most common type of computer. They are designed for individual users and are powered by a single microprocessor. They are also known as Personal Computers (PCs).

  • Characteristics: Small, relatively inexpensive, and designed for general-purpose tasks like word processing, browsing the internet, and entertainment.
  • Examples:
    • Desktops: PCs with a separate monitor, keyboard, and mouse.
    • Laptops/Notebooks: Portable all-in-one computers.
    • Smartphones and Tablets: Handheld computers with touch interfaces.

2. Minicomputers (Midrange Computers)

Minicomputers are multi-user computers that are more powerful and more expensive than microcomputers but less powerful than mainframes. They can support hundreds of users simultaneously.

  • Characteristics: Used as servers in a client-server network, for managing business applications, and for large databases. The distinction between powerful microcomputers (servers) and minicomputers has blurred in recent years.
  • Examples: Departmental servers used to run a specific business application, like an inventory management system for a single large store.

3. Mainframe Computers

Mainframes are large, powerful, and expensive multi-user computers. They are designed for high-volume, transaction-intensive applications and can support thousands of users and applications concurrently.

  • Characteristics: Known for their high reliability, security, and ability to process massive amounts of data (e.g., millions of transactions per second). They are used by large organizations for mission-critical applications.
  • Examples: Used by banks for processing financial transactions, by airlines for their reservation systems, and by large e-commerce companies for processing orders.

4. Supercomputers

Supercomputers are the fastest and most expensive computers in the world. They are designed for performing complex scientific and engineering calculations at extremely high speeds.

  • Characteristics: Instead of processing many transactions, they are optimized to perform a massive number of calculations per second (measured in FLOPS - Floating-point Operations Per Second). They often consist of thousands of processors working in parallel.
  • Examples: Used for weather forecasting, climate research, molecular modeling, and complex physics simulations.

Summary

Computers are classified based on their power and size into four main categories. Microcomputers (PCs, smartphones) are designed for individual users. Minicomputers serve the needs of departments or medium-sized businesses. Mainframes are used by large organizations for high-volume, mission-critical transaction processing. Supercomputers, the most powerful of all, are used for complex scientific and engineering calculations.

Key Takeaways

  • Computers are classified as micro, mini, mainframe, and supercomputers.
  • Microcomputers are personal computers designed for individual use.
  • Mainframes are built for high-volume, reliable transaction processing for large organizations.
  • Supercomputers are designed for extremely fast, complex scientific calculations.

Discussion Questions

  1. What type of computer would a large international bank use to process its daily transactions? Why?
  2. What type of computer would a scientist use to simulate the effects of climate change? Why?
  3. The lines between computer classifications are blurring. Is a modern high-end gaming PC a microcomputer or a minicomputer? Justify your answer.