Continues a stopped job in the background. This function is not available on all Unix shell's.
syntax: bg [-l] [-p] [-x] [job]

-l Report the process group ID and working directory of the jobs.
-p Report only the process group ID of the jobs.
-x Replace any job_id found in command or arguments with the corresponding process group ID, and then execute command passing it arguments.
job Specifies the job that you want to run in the background.

Example:
bg - Lists the current running jobs. Below is a listing of how to determine the type of job when looking at the job listing. % or %+ or %% for the current job. %- or - for the previous job.