When a job is put on hold, it will not be run until it receives the JOB_OFF_HOLD event or FORCE START. ON_HOLD is equivalent to stop the current execution process. 

Example: There are 4 jobs, say Job A, Job B, Job C and Job D. CONSIDER all these jobs reside in a box job NAMED box_1. The box job is started now. After starting the box job user immediately realized that there is a mistake in command script NAME in Job C. So, he put the Job C ON HOLD before it starts. Thus, he ensures the job will run proper way.

When a job is put on hold, it will not be run until it receives the JOB_OFF_HOLD event or FORCE START. ON_HOLD is equivalent to stop the current execution process. 

Example: There are 4 jobs, say Job A, Job B, Job C and Job D. Consider all these jobs reside in a box job named box_1. The box job is started now. After starting the box job user immediately realized that there is a mistake in command script name in Job C. So, he put the Job C ON HOLD before it starts. Thus, he ensures the job will run proper way.