start a remote job and then log off and return later
 

I know Ive read how some where but can't remember the terminology.

If I SSH to a remote system how can I start a command and have it running while I disconect and then re-connect later to check on it?

screen or tmux

at the end of command before you execute add & .

The HUP signal from disconnecting could kill the background job. Screen is what I use. I've never tried tmux (and apparently don't even have it to see what it does). I probably have a few dozen disconnected screen sessions spread over various servers right now.

If you need to do this with X Windows applications, there's Xvnc or Xtightvnc (an X Server in virtual RAM, accessible via a VNC viewer).

The job owner must have EXECUTE privileges on the credential or be the credential owner. For remote external jobs, the credential_name attribute is required. If this attribute is not set for local external jobs, default credentials are used.

Use
screen is another alternative IF you need to get back into that exact session.