OSC stands for Open Sound Control and here is the Link to Wikipedia.
Essentially it is a protocol for network communication used between digital music software, controllers or instruments, to send commands and values.
What do you need?
- a local network
- the Ip address and port of all your devices that want to talk to each other
How does it work?
You define a port(should be over 1000) where you start to send a message to another device identified by its IP-Addresses. This device gets the message by listening through its port. In most cases, it will use the UDP Protocol as a base layer to do this.
Why do we use it in theatre?
It is made for controlling shows so the protocol has a long history in theatre and a lot of soft and hardware made for theatre uses it.