What is LSD? Albert Hofmann's Invention, Explained

A man with LSD sign on May 5, 1967 in New York, New York. (Photo by Santi Visalli/Getty Images)

LSD (Lysergic acid diethylamide, or acid) permeates '60s and '70s pop culture -- it was the catalyst for psychedelic music, art, literature and fashion. Even if you never tuned in, turned on, and dropped out, you know a little about this mind altering drug created by Albert Hofmann and popularized by artists like The Beatles, Timothy Leary, and Steve Jobs. There's more to this drug than just hippies in the park with flowers in their hair. It's been used in government testing, and through its disciples Lysergic acid diethylamide has changed society in ways that we can't comprehend. People who've never experienced psychedelics might know that LSD is dispersed in tabs printed on blotter paper, but they don't know the research and development behind this mind expanding, trippy substance.