Introducing Python, 2nd Edition

Appendix A. Hardware and Software for Beginning Programmers

Some things make intuitive sense. Some we see in nature, and others are human inventions such as the wheel or pizza.

Others require more of a leap of faith. How does a television convert some invisible wiggles in the air into sounds and moving images?

A computer is one of these hard-to-accept ideas. How can you type something and get a machine to do what you want?

When I was learning to program, it was hard to find answers to some basic questions. For example: some books explain computer memory with the analogy of books on a library shelf. I wondered, if you read from memory, the analogy implies you’re taking a book from the shelf. So, does that erase it from memory? Actually, no. It’s more like getting a copy of the book from the shelf.

This appendix is a short review of computer hardware and software, if you’re relatively new to programming. I try to explain the things that become “obvious” eventually but may be sticking points at the start.

Hardware

Caveman Computers

When the cavemen Og and Thog returned from hunting, they would each add a rock to their own pile for each mammoth they slew. But they couldn’t do much with the piles, other than gain bragging rights if one was noticeably larger than the other.

Distant descendents of Og (Thog got stomped by a mammoth one day, trying to add to his pile) would learn to count, and write, and use an abacus. But some leaps of imagination and technology were needed to get beyond ...