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If this is the first time you've run DrRacket, it will ask you your preferred language, and the Scheme language level; the latter should be "Beginning Student with List Abbreviations". This language level provides the expected set of primitive operations and enables DrRacket to reject "legal" Scheme constructions that are not part of our introductory dialect. Read the DrRacket Tips and Traps page for helpful information on common mistakes, error messages, etc.
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The DrRacket window is divided into two halves. The lower half, or interaction window, is the Scheme "calculator". The top half, or definition window is just a text editor which is smart about indenting Scheme, and such. The execute button sends the contents of the definition window down to the interaction window, where they are actually evaluated.
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