AWS EBS Snapshots
Think of an EBS Snapshot as a way of backing up an EBS volume at a certain point in time.
Recommended best practice for creating a backup of an EBS volume is to detach the EBS volume from the EC2 instance (Not necessary but recommended) and then create the snapshot.
Once a snapshot of an EBS volume has been created then it is possible to copy the snapshot of the EBS volume to a different Availability Zone/ Region and attach the EBS volume to an EC2 instance in the new Availability Zone / Region.