There are many AFSK Digital modes each offering advantages over each other. Rather than me re-inventing the wheel, I will link to some excellent references from this page. You will see what modes you can use and what they might looks like and sound like on the bands.
Having a correctly set up transmitter is critical to Digital Mode Operation. Have a look at the excellent article by N1NKM on how to do this.
- List of Digital Modes on our sister site www.ham-interfaces.com
- List of Digital Modes and what they look like on a waterfall display by G4UCJ.
- PSK31 article on the ARRL website
- Excellent article this time by N1NKM where he shows you how to correctly set up your transmitter for optimal Digital Mode transmissions
- RSGB "Work the World with low power". Great article on what PSK31 is all about.