User's Guide - Key Concepts
Design time refers to the process of designing your AutoPlay application using the AutoPlay Media Studio design environment. Everything you do with AutoPlay Media Studio, from the moment you start the program, to the point where you are ready to actually generate or "build" your application, is considered work done "at design time."
Design time is where you, the designer, make the choices that will determine what your application will do, how it will do it, and what it will look like when it is done.
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