WYSIWYG is a commonly used acronym for What You See Is What You Get. Any application that shows you your documents exactly as they will be printed rather than showing markup or code. When used with reference to office applications,  WYSIWYG basically means that the interface explains to its users what the effects of various commands such as Print Preview, Fonts, Line and Section Breaks, etc, would be if they were used.

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The main benefit of such applications is that the user need not imagine the finial outcome; he can see it in front of him. Moreover, there are some notable features like Print Preview that allow users to adjust the document just before it is printed. MS Office programs are some of the most popular and widely used WYSIWYG applications.