Search by Kind One of the most useful ways to narrow down a search is by using the kind: keyword. This allows you to restrict your list of results to a certain file format. For instance, if you type time machine kind:pdf, Spotlight will pull up only PDF files containing the words time and machine. You can also limit your search to e-mail messages, music files, System Preferences, applications, and more.
While the original Spotlight recognized only a limited number of file types, the Leopard version can look for files created by specific applications, as well as certain file formats. Searching for kind:mp3 or kind:tiff will find files in one of those formats, and searching for kind:pages or kind:powerpoint will show only documents created in one of those programs. For a list of useful keywords, see “My Kind of Keyword.” But remember, for the keywords to work, you must have the appropriate categories enabled in Spotlight’s preferences.
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