Cron is a time-based job scheduler in Unix-like operating systems. It allows users to run scripts or commands automatically at specified intervals, such as daily, weekly, or monthly. This automation helps manage repetitive tasks without manual intervention. Users create a configuration file called a crontab, where they define the schedule and the commands to execute. Each line in the crontab specifies a time and the corresponding command, making it easy to automate system maintenance, backups, and other routine tasks efficiently.