A hipster is now basically just a caricature of a liberal, urban European student. The hipster lifestyle started in the late 90s/early 00s as reaction to the MTV/TRL/popstar/celebrity worship/fast food consumer culture that peaked in America right before 9/11. Some people were trying to get away from all of that, and instead shopped at thrift stores, started growing their own organic food, read nonmainstream literature, listened to indie music etc, and didn't really fit in with the average joe, and their intentions were at least somewhat authentic in the beginning, unlike most hipsters now. Its origins were mostly on the west coast like grunge was, because that area already has some slight counter-cultural tendencies. Eventually it was picked up and marketed to the youth as an image and a lifestyle so they could be labeled and to get them to buy stuff, just like they did with grunge in the 90s. Today's stereotypical hipster is an exaggerated version of this earlier hipster.
Today's hipsters are different than the ones in the 90s