The format section in API information describes a format name.
For example, for the Retrieve Job Description (QWDRJOBD) API, the format described is JOBD0100 Format. Listed within the format are the individual fields that contain the attributes of the job description. The offset in the Dec (decimal offset) column for the hold on job queue field (hold parameter on the Retrieve Job Description command) begins at decimal offset 76.
The fields in the format do not occur in any particular sequence. You have to scan the format to determine what you want.
The Retrieve Job Description (QWDRJOBD) API has only a single format; other APIs may have multiple formats where each format has different levels of information. With multiple formats, a format name parameter allows you to specify which format you want to retrieve.