What’s a Programming Language?
Directions to the nearest bus station can be given in English, Portuguese, Mandarin, Hindi, and many other languages. As long as the people you’re talking to understand the language, they’ll get to the bus station.
In the same way, there are many programming languages, and they all can add numbers, read information from files, and make user interfaces with windows and buttons and scroll bars. The instructions look different, but they accomplish the same task. For example, in the Python programming language, here’s how you add 3 and 4:
| | 3 + 4 |
But here’s how it’s done in the Scheme programming language:
| | (+ 3 4) |
They both express the same idea—they just look different.
Every programming language has a way to write mathematical expressions, repeat a list of instructions a number of times, choose which of two instructions to do based on the current information you have, and much more. In this book, you’ll learn how to do these things in the Python programming language. Once you understand Python, learning the next programming language will be much easier.