A Cron Job is what you set up if you need a script or piece of code to be executed sometime in the future, once or at intervals.
Use cases and Examples
Cron jobs are usually set up to run tasks at regular intervals. This includes things like backing up data on a server or sending out emails.
Operating systems like Linux allows you to do this from the command line. In this case the script to be run is scripted using shell.
Without cronjobs, tasks that need to recur regularly will require a human, either the end-user or developer, to trigger the task.
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