With amateur radio operation there are several types of digital modes available to all operations.

These modes include:

History of PSK!

History of RTTY!

History of SSTV!

There are several programs you can find on the internet by searching the web. Which are:

{MIXW}which includes all modes of transmission.

{Multi-PSK} does the same thing for all modeswith extra modes of operation.

{FLdigi} Allows different modes of digital transmission.

{MMSSTV} For slow scan tv transmission.

{MMRTTY} For Radio teletype transmition.

These are a few examples you can find and play with to have digital comunication.If you go to the Ham links page you will see more about these programs and more.