Why does Microsoft Word convert words between asterisks to bold text when I type them?
Most versions of Microsoft Word for Windows and Mac OS X have an “AutoFormat As You Type†option. This feature is intended to take care of common formatting chores for you automatically. For example, Word can convert two hyphens to a dash, transform typewriter-style “straight†quotation marks to typographer's “curly†quotation marks and turn Web addresses into live hyperlinks.
The program also assumes that a word typed between two asterisks is meant to be in boldface type and a word between two underscore characters is intended to be in italic type. If the program automatically converts a word to bold or italic against your intentions, press the Control-Z (Windows) or Command-Z (Mac) keyboard shortcut immediately to reverse the automated change.
You can make a more permanent adjustment to Word's AutoFormat behavior in the program's settings. Microsoft has instructions for the past few Windows editions here and the most recent version of Word for the Mac here. Instructions for older versions of Word for Mac OS X are here.
