You've got a crick in your neck that just won't go away. Or you've pulled something playing with your kids. Or work's been crazy busy lately. Whatever the reason, a massage sounds like—and usually is—one of the best ways to decompress and reset yourself when you're stressed. There's almost an unlimited number of types to treat just about any ailment, and they're all pretty different. Before you book your next (or first) appointment, check out this guide to get the basics.