The Mother of All Demos
In 1968, some researchers from Stanford Research Institute (SRI) gave a demo of some of the computer work they had been developing. SRI was a Fred Terman initiative (see: History of Silicon Valley 1891-1956) and quasi-independent research lab that did work that didn't entirely fall under faculty work.
Inspired by Vannevar Bush's As We May Think, Doug Englebart and his colleagues demoed new computer functionality that had never been seen before. They wanted to make Bush's memex a reality. Unfortunately, many of these inventions would take a decade to make it to commercial viability (namely, graphical user interfaces developed by Microsoft and Apple in the 1980s).
The computer mouse
Graphical User Interfaces and windowing
Word processing
Hyperlinks
Collaborative real-time editing (the demo was in San Francisco's Civic Auditorium, and two custom modems connected the demo site to a lab in Menlo Park)
Video conferencing
Without further ado, here's a shortened 5-minute highlight reel of the demo. If you're interested, here's the full one-hour+ version.
"We're going to try our best to show you, rather than tell you about this program"