There are five categories: Clean Glassy Crunch Blues Metal, each of which has five settings, numbered 1 thru 5. Right away, you can switch between twenty five amp models that are pre-loaded into the amp. Indeed, the "Quick Start" mini pamphlet shows several graphics (in case you just bought a computer based modeling amp and can't read ) the first of which is a drawing of a guitar, cable, the Bias Head and then several devices from the amp's outputs- one of which is a speaker cab. I've had it for three days now and so far I'm very impressed! It didn't start out that way, although that was, by and large, my own fault ("my Bad.") as they say! I purchased it from Sweetwater and their main video portrays one of the Sweetwater Exec's saying that right out of the box, it's loaded with 25 amp models and is, essentially, plug and play. There aren't really any complete reviews on this amp here on Strat Talk, and although there are reviews and YouTube videos / Company reviews / videos on it, I always like a 'real world' review from an end user, without all the fluff and "Now's my chance to impress you with my virtuosity." type stuff that sometimes occurs. Well, on Friday the very harried FedEx guy dropped this off at my door! I intend to do a review, in segments, with more pics and perhaps, if I get the tutelage, some sound files.