EBS

Block storage, mountable and persistent.

• Network attached to EC2 instances.
• EC2 instance can be EBS-optimized, by having dedicated network throughput for volumes.

Can snapshot volume state.

• snapshots work iteratively, saving any blocks on the disk that have changed since the last snapshot
• S3 is usually the backend storage service for storing snapshots
• data transfer across regions has cost associated with the one-time operation