I'm much more of a fan of interactive digimodes than the automated ones where you click a button, and the
computer does it all for you.
With interactive digimodes, you actually learn things about the other station.
RTTY (Radio teletype) is one of the oldest, and probably has the most recognisable audio. Text is converted into 1s and 0s, each of which is then sent as two audio tones.
PSK comes in varying speeds and bandwidths. One of the most common is PSK 31, which takes 31Hz of bandwidth.
Olivia is one of my favourites. It is a multi-frequency mode, with lots of options for bandwidth and number of tones used, which provides speed if the conditions allow.
Scheduling interactive contacts
Because so many people are using FT-8, there aren't as many people using these interactive digimodes. And because there aren't as many people using them, it's harder to make contacts. And because it's fairly crushing to be calling for a QSO for minutes on end, people then go back to where they know they can make a contact - FT-8. Which compounds the problem.
I want to help keep these modes alive, so I've created a very simple chat service to help people schedule contacts. (Ideally, we shouldn't need an Internet-based service to schedule contacts, but maybe this is the way to do it for now.
It is at https://digimode-chat.g7vrd.co.uk/. It doesn't have a database, it doesn't record anything or keep history. Enter your callsign, and say your location and what modes you're interested in, and see if anyone else is there. Don't forget to stay logged in - it won't really work if everyone just logs in for 2 minutes, and quits. The whole point is that people idle.