MTV's concept was simple enough: play music videos 24 hours a day, 7 days a week and have them hosted by the television equivalent of the radio DJ, christened VJs. MTV's original five VJs were Nina Blackwood, Mark Goodman, Alan Hunter, J.J. Jackson and Martha Quinn, and during the early 80s they became as recognizable as old school TV fixtures like Walter Cronkite and Ed Sullivan had once been.
A mad scramble by established broadcast and cable channels followed as they attempted to get on the music video boat before it pulled away from the pop culture dock. Everyone from HBO (Video Jukebox) to NBC (Friday Night Videos) to ABC (ABC Rocks) dove into the fray along with seemingly countless other national and local stations. None of them were able to reproduce the MTV magic and within a decade most had thrown in the towel.
It should be noted that while MTV was clearly forging a new pathway through popular culture, one that was trumpeted as being cutting edge, fact is that at the beginning they almost completely ignored black artists. It wasn't until Michael Jackson came along and kicked in the door that MTV became artistically integrated.
Post mortem editorial:
Ironically, after vanquishing all comers, MTV itself decided to pull out of the 24/7 music video business during the 90s, moving slowly but inexorably into talk shows, game shows and garish, self-indulgent "reality" programming which pandered to the growing swarm of consumer-youth. In the process they left behind any semblance of integrity or cultural importance. The network continues to wallow in the shallows to this day with mind-numbing fare like "Jersey Shore" where a bunch of no-talent nobodys from nowhere with nothing to say are followed around for no discernible reason.
The first video ever played on MTV: The Buggles - Video Killed the Radio Star