What's the word Copyright and `(C)' mean?
Solution 1:
Wikipedia describes it in some detail:
Copyright are exclusive statutory rights to exercise control over copying and other exploitation of the works for a specific period of time. The copyright owner is given two sets of rights: an exclusive, positive right to copy and exploit the copyrighted work, or license others to do so, and a negative right to prevent anyone else from doing so without consent, with the possibility of legal remedies if they do.
Basically, any work someone produces (e.g. a book, a song, some software, etc) may not be copied by anyone else without the author's permission.
The year in which the work is produced, as noted in the copyright declaration, is important, because copyright only lasts for a certain number of years, which varies by jurisdiction. Hence lots of old books are now available on the internet for free, because their copyright has expired.
"©" (often written as "(C)") is just an abbreviation for "copyright". See also the article on the copyright symbol.
Solution 2:
To expand on Steve's answer:
©2001 means the countdown to the end of copyright starts in 2001.
©2001-2010 means the countdown to the end of copyright starts in 2010 (at least for some of the content)
Websites use the latter because their content and construction generally changes frequently. Things are added and removed on a regular basis, so the copyright on the new content/coding/images is being refreshed.