Steptronic was correctly described above (no surprise since it's BMWs definition). However, the Steptronic tranny program will upshift to prevent engine damage, i.e. you cant leave it in second and just run the engine at redline- it WILL upshift. Also, it will downshift when coming to a stop if you dont. For example, coming to a stop from 5th, and you dont downshift, it will automatically downshift to 3rd, then 2nd, to keep you from stalling when you start to go again. So basically, its a little bit of manual and auto. HOWEVER, it is not a replacement for a true manual or SMG transmission, since it doesnt allow for "heel and toeing" throttle blips on downshifts, and because it will take over it you arent paying attention.