In addition, some programs offer options to have specific selections of text be set to a given language. To overcome this problem, you can either temporarily change the system-wide spell check options, or do this for individual applications' spell check settings either globally or for a specific spell check session. TextEdit's Language chooser is in the spell checker.
Though this is convenient, there may be times when in typing documents you will need to use phrases or paragraphs in different languages, and having the spell checker in one language will not work. The language setting will not only set the system's display language, but also set up the various spell checkers used in word-processing programs like TextEdit, Pages, and Safari. This will set the system-wide spell checker to the desired language, and also cue other applications such as Microsoft Office to set their languages accordingly at installation time, if supported. When you initially set up your Mac, you will be asked to select one of several supported languages as the default language to use.
