You might also want to consider whether you want to perform using your guitar or perhaps record with it. If so then it's worth looking for an acoustic guitar with onboard electronics, as they'll enable you to plug it into an amp or recorder in the same way you can an electric guitar.
Acoustic guitar pickups, simply put, are devices which translate the sound of your acoustic guitar into an electrical signal. This signal goes through your guitar cable and then into any of the best acoustic amps or a PA speaker. There's more science to it than that, but we won't go into it in too much depth here.