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Documentation / Mathematica / Front End / Menu Commands / Help Menu /

Master Index...

FilledSmallSquare Master Index opens the Help Browser with the Master Index radio button selected.

FilledSmallSquare The Help Browser lets you access a wide range of notebooks and other material to get help while you are using Mathematica.

FilledSmallSquare See The Mathematica Book: Section 1.3.8 and Section 1.3.9.