To understand how this story got started, it's important to understand what Gore actually said, how his words have been maliciously misinterpreted, and what his actual contributions were as a politician.
What Gore Really Said
Here's what Gore actually said, during an interview with CNN's Wolf Blitzer:
"During my service in the United States Congress I took the initiative in creating the Internet. I took the initiative in moving forward a whole range of initiatives that have proven to be important to our country's economic growth and environmental protection, improvements in our educational system."In context, it's obvious that Gore was only claiming to have moved the Internet forward at the governmental level, by offering support and resources to help it grow. Unless he was also claiming to have invented the environment and the economy!
In fact, what Gore really meant is so obvious that those who have attacked Gore over the years have felt the need to misquote him. "Al Gore says he invented the Internet" sure does sound ridiculous... except that he never said it.
What Gore Really Did
Is it true that Gore "took the initiative in creating the Internet?" Bob Kahn and Vint Cerf, who invented the TCP/IP protocol that is at the core of all Internet communication, certainly think so:
"As the two people who designed the basic architecture and the core protocols that make the Internet work, we would like to acknowledge VP Gore's contributions as a Congressman, Senator and as Vice President. No other elected official, to our knowledge, has made a greater contribution over a longer period of time."Among other things, Kahn and Cerf were referring to the High Performance Computing and Communication Act of 1991, originated by then-Senator Gore, which provided funding and resources for the growth of the Internet.
To summarize: no, Al Gore did not invent the Internet. I reserve that term for the people who figure out how a thing should work, at a practical, nuts-and-bolts technological level. But Gore never claimed to have invented the Internet. He did claim to have played a role in creating the Internet as we know it - which is quite true.
For more information, see CNN's transcript of the Blitzer interview, Wikipedia's Al Gore entry, Bob Kahn and Vint Cerf's press release on Gore's remarks, and a somewhat less Gore-friendly article in the Washington Post which nevertheless concludes that Gore's contributions were indeed significant.