What is a full backup?

A full backup is a backup of every file on a file system, whether that file has changed or not.

The alternatives to a full backup are incremental backup and differential backup.

A full backup takes longer to accomplish and requires the most storage space on the backup media, but it also provides the quickest restore times.

A full backup should be performed weekly or monthly on production systems, along with daily differential backups.

A full backup should also be performed before any major planned changes to a system.