Programming languages like Pascal, C, or BASIC are called Imperative Languages.

One feature they all have is an assignment statement which gives values to variables. Then these variables are use to compute things statement by statement.

Functional languages don't compute using variables and assignment statements.

Rather, they apply functions to values to compute answers.

Scheme is a functional programming language.

It is a dialect of the first functional programming language, Lisp.

Scheme (and other functional programming languages) are used extensively in AI, natural language processing, speech recognition systems,

But its real claim to fame is its ability to express computations in a concise, elegant way.

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