In order to understand or speak about anything one needs a vocabulary. One needs English, or Danish, words to speak one of those two languages. When you speak about programming, you must first realize that programming is expressed in a programming language. The written expression of a programming language is called code. Consequently when we speak of code, our vocabulary, our subject matter terminology must be expanded somewhat. That is the aim of this section.

Code, therefore, is a program, or parts of a program, written in a language understandable by the platform it is meant for. It is typed into a text editor and saved as a textfile with a name according to the rules of the language.

In a natural language a building block of the language is a sentence. Sentences consist of words, long or short. The words are built from characters, usually in themselves meaningless, but with some phonetic implication.

In a programming language, the sentences are called statements. Statements consist of expressions that are built of variable(s) and value(s) combined by operator(s). In a running program an expression always has a value.