What is a PID number?

Linux and Unix-Like Red Hat
1

What is a PID number?

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Each time a process is created it gets its own unique number to refer to it by. That's a Process ID, or "PID" for short.

3

Thank you!!.
And Why are these numbers useful when you run processes in the background?
Please?

4

So you know which jobs are running in the background, should you need to do something with them.

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