Introducing Python, 3rd Edition

Chapter 2. Types and Variables

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A good name is rather to be chosen than great riches.

Proverbs 22:1

Computer programs consist of commands (often shorthanded as code) and data. This chapter introduces the basics of how computers handle data, and how Python is a bit different from many programming languages.

A Caveman Computer

Figure 2-1 is a drastically simplified diagram of a typical computer’s components.

Figure 2-1. Computer components

• The central processing unit (CPU, or “chip”) is the brains of the operation. Most computers now have multiple CPUs, and we’ll say more about this in Chapters 23 and 29.

• The random access memory (RAM) is the fast but limited storage area.

• A disk stores much more data than the RAM does, but is thousands of times slower.

• Common local input devices include keyboards, touchscreens, mice, ...