Crossfit is from Santa Cruz and is a combination of a lot of different stuff, the mix of which has changed over time. It's different depending where you go because there has never really been a standardized specific thing that it is and gyms are entirely independent. Gyms license the brand name, there are certification classes run by corporate, there is a very active internet community and something of a consistent philosophy, but what any particular gym actually does as far as training has always varied wildly and that's been from the very beginning.