Process and Job

Processes and jobs sound similar; however, they are different concepts. Jobs are processes generated by a terminal (shell) while processes are any programs running on a computer. In other words, jobs are defined from a user point of view while processes are defined from an operating system point of view.

Job ID

Jobs are separately managed by each terminal. As Linux is a multi-user operating system, the same system can be accessed by multiple terminals. Each job generated by a terminal has a unique ID called job ID. It is unique within the same terminal but the same ID number can be used for other terminals.

Process ID

Each process also has a unique ID called process ID. Each process is unique within the same operating system (unique even among different terminals connecting to the same operating system). When a job is created, a process ID is assigned to the job. Thus, you can manage the job using either job ID or process ID. Process IDs are also assigned to system-generated processes which don't have job IDs.