Backing up vCenter is the process of creating a copy of the vCenter Server database and configuration files. This is important because it allows you to restore your vCenter Server in the event of a failure. Without a backup, you could lose all of your virtual machines and data.
There are several different ways to back up vCenter Server. You can use the vSphere Client, the vSphere Web Client, or the vSphere API. The method you choose will depend on your environment and your needs.