A Web Browser is a client program that communicates with Web servers throughout the Internet, primarily using HTTP (hypertext transfer protocol) to make requests and submit information on behalf of the Browser user. Browsers locate Web pages by means of a URL (uniform resource locator), the Web address that begins with http: for HTTP access. Many Browsers also support a variety of other URL types and their corresponding protocols, such as ftp: for FTP (file transfer protocol), rtsp: for RTSP (real-time streaming protocol), and https: for HTTPS (an SSL encrypted version of HTTP used for security purposes.) In order to view a Web page, the user types the URL into the Browser's Address field. The file format for a web page is usually HTML (hyper-text markup language.) Most Browsers natively support other formats in addition to HTML, such as the JPEG, PNG and GIF image formats. Through the use of plugins, Browser functionality can be expanded to support additional formats. The combination of HTTP content type and URL protocol specification enables Web designers to embed images, animations, video, sound, and streaming media into a Web page, or to make such features accessible via the Web page. Browsers functions are accessed via the toolbar, which can be configured for user preferences. Common toolbar functions include bookmarking to save the URLs of favorite Web sites, navigation buttons, a history list that stores visited sites for a pre-determined length of time, security settings and other command buttons. |