Many features which make the WWW appealing as a method of serving information are also the features which create barriers for users of alternative access systems. The Web is a seemingly limitless system of information servers worldwide, which are tied together by hypertext links. Through hypertext links, related information or documents can be retrieved without regard to their location. Browsers are application programs which run on the user's computer and receive and display the Web HTML documents.
Browsers provide the user interface for the Web.
While the documents served over the Web or standardized, the browsers and therefore the user interface are not. A large number of Web browsers are based on NSCA Mosaic, the original graphical Web browser available free on the Internet. The leading alternative is Netscape Navigator. Internet access providers frequently supply proprietary browsers with their service. The leading non-graphical Web browser is Lynx which is available for Mac, DOS and Unix platforms.