Backups are standalone copies of your data that are kept in a different location from your VM. A single point of disk failure does not cause catastrophic data loss. VM backups can be moved to the cloud, a separate location, or offsite for safe storage. Backup have the ability to recover a entire VM or individual files or applications. It also allows you to only back up data that has changed since the last backup so you can save storage space.
Snapshots are an instantaneous "picture" of your server's file system at a certain period of time. Usually Snapshots are used when you are performing an update that could harm your system. But snapshots are not a full copy of a virtual hard disk. If the virtual disk is deleted or storage or infrastructure fails, snapshots cannot restore a VM. Snapshots can also affect the performance of your VM if snapshots are kept running for a long period of time. It is recommended that only using 2 to 3 snapshots in a chain and never running a snapshot for more than 72 hours to keep performance high.
break down of the differences between backups and snapshots
|Stored in differernt location from original data||Stored in the same location as original data|
|May have differences based on when the backup started and ended||A "picture" of your server at a period|
|Long Term||Short Term|
|Long time to copy data||Quick to copy data|
|Use for Data Lose Restore||Use for OS or System Update|