In one sentence
Regions and AZs describe placement and failure isolation, Edge describes nearby user entry points, and Global / Regional / Zonal describe service and resource scope.
Comparison
| Concept | Meaning | Typical examples |
|---|---|---|
| Region | An independent geographic area containing multiple AZs | ap-northeast-1 |
| Availability Zone | A failure-isolation boundary made of one or more discrete data centers | Multi-AZ designs |
| Edge Location / PoP | An edge network site near end users | CloudFront, Route 53, Global Accelerator |
| Global Service | Management is not centered on one selected Region | IAM, Route 53, CloudFront |
| Regional Service | Resources and operations belong to one Region | DynamoDB, SQS |
| Zonal Resource | A resource placed in a specific AZ | EC2, EBS, Subnet |
Key boundaries
- A VPC is regional while a subnet is zonal.
- EC2 is viewed by Region, but an instance lives in an AZ.
- A globally unique S3 bucket name does not make the bucket a global resource.
- Switching the console Region can make regional resources disappear from the list without deleting them.
- Choose a Region by compliance, latency, service availability, then price.
Exam traps
Multi-AZ is not Region-level disaster recovery, Multi-Region does not automate replication or failover, and an Edge Location is neither an AZ nor a normal EC2 deployment location.