The laser is 50 years old today

It's hard to believe now, but Theodore Maiman's discovery was turned down from scholarly publication when he first submitted it! At the time there was a lot of work being conducted on maser (microwave amplification by stimulated emission of radiation) and the journal Physical Review Letters thought that Maiman's article was a retread of too many others. But before long researchers - and soon afterward the rest of the world - agreed that the laser which Maiman created on May 16th 1960 using a ruby rod was an entirely different gimmick. Fifty years later and lasers are everywhere around us: in CD and DVD players, in your doctor's office, maybe even in your shirt pocket.

CNN has a great retrospective about a half-century of the laser. And if you want to know how a laser differs from a flashlight, HowStuffWorks hosts a terrific essay about the laser's inner workings.