The primary job of the DNS is to convert domain names to IP addresses, which is how people navigate the Internet. DNS does a lot more than that, but that’s the basic concept. As you can imagine, employees at a DNS company spend a good amount of time explaining this function. Everyone has their favorite analogy. I’ve found the best to be “DNS is like the phone book for the Internet. You type in a name and it figures out the number.”

If DNS is the phone book, domain names are the listings. To that point, today is the 25th anniversary of the first ever registered domain in .com, the top-level domain that accounts for the vast majority of Web sites on the Internet. In particular, the Web sites that receive the most traffic.

As we reflect today on the unprecedented growth the Internet has seen, and think about that first-ever registered domain – Symbolics.com – here’s some background on .com domains from a San Francisco Chronicle article published today.

• In 1985, only six entities registered a .com, one of six top-level domain names created a year earlier in a reorganization of the early Internet’s naming bureaucracy. At the time, .cor (short for corporate) almost beat .com as the designation for commercial Internet addresses.
• By 1992, fewer than 15,000 .com domains were registered, but the number would flourish after Web browsers brought mainstream consumers onto the Web.
• Today there are 84 million domain names, including 11.9 million e-commerce and online business sites, 4.3 million entertainment sites, 3.1 million finance-related sites and 1.8 million sports sites.

The first ten registered .com domains:
Symbolics.com - March 15, 1985
BBN.com - April 24, 1985
Think.com - May 24, 1985
MCC.com - July 11, 1985
DEC.com - Sept. 30, 1985
Northrop.com - Nov. 7, 1985
Xerox.com - Jan. 9, 1986
SRI.com - Jan. 17, 1986
HP.com - March 3, 1986
Bellcore.com - March 5, 1986