First, &
This is used at the end of a command to put this command in the background.
Second, "Ctrl" + "Z"
You can place a command that is executing in the foreground in the background and pause.
Third, Jobs
See how many commands are currently running in the background.
Iv. FG
The commands in the background are moved to the foreground to continue running.
If there is more than one command in the background, you can use FG%jobnumber to bring up the selected command,%jobnumber is the ordinal of the command that is being executed in the background through the Jobs command (not the PID ).
V. BG
A command that pauses in the background changes to continue execution.
If there are multiple commands in the background, you can use BG%jobnumber to bring up the selected command,%jobnumber is the ordinal of the command being executed in the background through the Jobs command (not PID).
Above transfer from: http://blog.sina.com.cn/s/blog_673ee2b50100iywr.html
Use of &/JOBS/FG/BG commands under Linux (RPM)