You may not know the name Ward Christensen, but he was a key figure in what led to the modern internet. He co-created BBSes in 1978.

Their new system allowed personal computer owners with modems to dial up a dedicated machine and leave messages that others would see later. The BBS concept represented a digital version of a push-pin bulletin board that might flank a grocery store entrance, town hall, or college dorm hallway.

In many ways BBSes led to the modern internet. This is a nice overview of his accomplishments by Ares Technica.

LINK: Ward Christensen, BBS inventor and architect of our online age, dies at age 78