cron - Wikipedia
The software utility cron also known as cron job is a time-based job scheduler in Unix-like computer operating systems. Users who set up and maintain software environments use cron to schedule jobs...
Crontab.guru - The cron schedule expression editor
Cron job failures can be disastrous! We created Cronitor because cron itself can't alert you if your jobs fail or never start. Cronitor is easy to integrate and provides you with instant alerts when things go...
CronHowto - Community Help Wiki | Alternatives to Cron
Cron is a system daemon used to execute desired tasks (in the background) at designated times. A crontab file is a simple text file containing a list of commands meant to be run at specified times.