DrRacket provides support for multiple editor modes. Tools register modes via drracket:modes:add-mode. Each mode is visible in the Modes submenu of the Edit menu. Initially, DrRacket only supports two modes: Racket mode and text mode.
DrRacket automatically selects a mode for each open file based on the file’s extension. If the file ends with .txt, DrRacket uses text mode. Otherwise, DrRacket uses Racket mode.