Postgres, a powerful open-source relational database management system, can be extended to function as a cron server using the pg_cron extension. This allows users to schedule periodic tasks within their Postgres database, such as triggering webhooks at fixed times or intervals. The process involves enabling the extension and granting access to non-superuser roles for scheduling jobs. Additionally, another extension called pgsql-http can be used for sending HTTP requests from Postgres functions. This combination of features makes Postgres a versatile tool for managing various types of scheduled tasks.