When connected and some documents are shared between some users. That is when you can edit your documents together. A session is bound to one IRC channel.

If you select a buffer (jEdit term for an open file) to use it in your session, its called a shared buffer, shared document or just document.

The people which take part in a session. They are a subset of the people in the IRC channel of the session.

The one who is the first in a session, the one who starts it, will automatically get the role of the master. Only the master defines what documents are shared. Note: this role can change during the session, if a master wants to leave but the session should stay on.

All other user, who are not master, are called clients.

To edit a shared document, you need write access for it. You can retrieve it, if there is currently no one having the write access for that document. And when you are finished with editing, you can release the write access, so that others can grab it. (Write access might sometimes get called mutex).

A session can be blocked for a short period of time. This is to ensure synchronization when a user is joining and needs to get the most up-to-date version of the documents.