What is Cron?
Cron is a time-based job scheduler on Unix-like systems, configured with a five-field expression — minute, hour, day of month, month, day of week — that defines when a command should run. It has been the standard way to schedule recurring tasks (backups, cleanup scripts, reports) since the 1970s.
Example
0 9 * * 1-5 runs a job at 9:00 AM every weekday.
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