More and more of us use Facebook these days, and it is a convenient means of exchanging news on a fairly trivial level. However, recent experiences have reminded me that there's no such thing as privacy, once you go online. This especially applies to Facebook.
Search
Search is a module for searching "core" content along with certain registered modules. You put in a word or two and it gives you back matching, relevant results.
You can see the search module in use in the default templates, like on this page. Simply put {search} in your template, where you want the search form to appear. If you want the results of a search to appear on a different page, you can specify this with the parameter resultpage='page alias'.
For more information, see the Search module in the Admin Panel, in the Extensions menu.