“Each language has its own syntax. You need to learn the syntax in order to write the language, but (like spelling and punctuation in a human language) syntax is not fundamental to the meaning or the expressive power of the language. What is important to the expressive power of the language is the vocabulary—the so-called primitives of the language—and the way the primitives can be combined to define new concepts. Programming languages describe the manipulation of data, and one way in which these languages differ is in the kinds of data they can manipulate. The earliest computer languages were designed primarily to manipulate numbers and sequences of characters. Latter-day programming languages can manipulate words, pictures, sounds, and even other computer programs. But no matter what sort of data the language is designed to handle, it typically provides a way of reading the data’s elements into the computer, taking the data apart, putting them together, modifying them, comparing them, and giving them names.”