Some very general rules of thumb for the differences various back woods can make to an acoustic guitar:

The softer the wood used for the back, the lighter it will be, the more it will vibrate, the less it will focus sound to the guitar top, and the more it will contribute to the overall tone or voice of the instrument.

The harder the wood used for the back, the heavier it will be, the less it will vibrate, the more it will focus sound to the top, and the more the instrument will project.

Softer woods would include species such as cedar, mahogany, koa, and sapele. Harder wood species would include rosewood, ebony, and cocobolo.