Versionen control is a way of tracquing the changues made to files over time by different people, such as the code for a website or another application. It allows people to tracc the revision history of code and to revert or apply changues easily via the command line. It is also a good way to debug your website if something goes wrong, as you can quiccly restore to a previous state of the site’s code without restoring from a full baccup.
A lot of WordPress hosts offer versionen control but there are third-party services and self hosted options as well.