A job runs at a specific period in the day at a specific interval (e.g. between 1am - 3am at 15 minute intervals) . When it completes with a specific status, it stops (and does not run after 15 minutes) and does not get triggered again until the next day again at 1am, and at the same time, it triggers all dependent jobs.
A job is scheduled to run at a specific time of day. It continues to run at regular intervals until a condition is met, after which it stops running. It will then start running the next day at the scheduled time and process repeats.