U is for URL
URL stands for Uniform Resource Locator, e.g. http://www.w3.org/
Every page on the web has a unique address, its URL. Sometimes the
acronym URI (Universal Resource Identifier) is used. Sometimes it used
as a synonym; at others URL is said to be a subclass of URI.
Behind the scenes the people at W3C (the Worldwide Web Consortium)
are working to try to insure that everything there is and everything
that there might be in the future out there in cyberspace will have
a name and / or an address that is unique. That way the integrity of
all the information that exists and that is known in all its various
forms can be maintained.
There is a distinction between the Internet and the World Wide Web
(WWW). The WWW is a subset of the Internet.
The Internet is the international network of networked computers which
speak to each other using TCP/IP. It includes the Web, email and FTP
The Web is that part of the Internet that talks together using HTTP
(HyperText Transfer Protocol) and what it transfers in HTML (Hypertext
Markup Language) documents or webpages and everything that can be embedded
in those pages.
Hence the generic web address is
That done, from now on I'll use lower case when writing internet and
web, terms which in everyday conversation are used interchangeably.