The term for addresses on the Web; the acronym stands for Universal Resource Locator, which need never be used.
If at all possible, use a contrasting typeface (such as italics) to distinguish between a Web address and the rest of the sentence. Never allow a Web address to break over two lines with a hyphen; break if necessary using a required soft return following a slash or other mark of punctuation that is part of the address. Try to avoid using a Web address at the end of a sentence, where the period ending the sentence may be seen as part of the address.
It is not generally necessary to include “http://www.” as along as the Web is specified: The full story is available on the Internet (uga.edu/columns/). Be alert, however, to possible confusion when the URL does not begin with “www,” and specify the “http://” if readers will be otherwise misled.