WebCrawler and other search engines do examine or search the entire document against your query. Gopher is an Internet software application that organizes information. Prior to the World Wide Web, gophers provided an easy menu-driven system to browse the Internet. But with a gopher you could only view gopher files and there was no graphical capability. With the advent to the World Wide Web, gopher sites can now not only be viewed through gopher software but also through WWW browsers like Netscape or Lynx.
Internet is the name given to the complex world wide network of computers.
Hierarchy is a system in which items are ranked above or below each other. For example the President of the United States is higher up in the hierarchy than the Vice President. Hierarchies provide ways of organizing and thinking about information in a systemic structure. Indexing is the process that makes it easier to retrieve information from a database. Computer indexes act as pointers to information just like an index does in a book.