The Internet Turns 40...

Forty years ago today, the Internet may have uttered its first word.

Twenty years later, Kleinrock chaired a group whose report on building a national computer network influenced Congress in helping develop the modern Internet. Kleinrock holds more than a dozen patents and was awarded the National Medal of Science last year by President Bush.

In this interview with CNN, the 75-year-old looks back on his achievements and peers into the exciting and sometimes scary future of the Web he helped create.