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A keyword is an identifier with a special meaning and function in a programming language. Keywords include reserved words (such as begin or while) and modifiers (such as reintroduce or absolute) (see also Free Pascal reserved words).

Lazarus will usually display keywords in Pascal text files (source code) in bold black characters using syntax highlighting. Use [IDE options|Editor|Colors] to change.

Some very common Free Pascal words like read or write, are in fact procedure names, not keywords.