Relay docs
There isn't any software documentation for relays.
How many teams still use relays?
In 2019, 187 teams instantiated 270 relays.
They are a supported feature and should be added to the documentation
I agree with the fact that they need documentation, and more docs could increase the amount of users. However, what are FRC uses of relays? What relay-based FRC products exist?
A handful of teams use relays to power their compressor rather than the PCM so they can use an auto resetting breaker. Relays are also an easy way to turn an LED light ring on and off.
Relays big use are in various custom circuits
Relays can also be used for low current motors.