For example, the QuickTime plug-in enables Web browsers to display QuickTime movies. Internet plug-ins enable applications to display files that are of the specific types handled by those plug-ins. Plug-ins are software that can be incorporated into a Web browser when it opens (thus, the term plug-in). Safari and other Web browsers use plug-ins and helper applications to expand their capabilities so they can work with files they don't natively support. Safari can't work with all these file types directly, and fortunately, it doesn't have to.
In addition to HTML, JSP, GIF, JPEG, and other files that are used to present a Web page, there are graphics, movies, sounds, PDFs, and many other file types you can open and view. Many file types are available on the Internet.
