The AWS Global Infrastructure consists of Regions, Availability Zones (AZs), Edge Locations.

AWS Region

  • An AWS Region is a distinct physical location in a geographic area of the world consisting of two or more AZs.
  • At the time of writing, there are more than 20 AWS Regions with more regions planned in the future.
  • Data replication can be enabled and controlled across regions.
  • The communication between regions depends on the AWS backbone network infrastructure.

Availability Zones

  • At the time of writing, there are more than 60 Availability Zones.
  • An AZ is made up of one or more data centers.
  • An AZ is built for fault isolation and therefore designed as an independent failure zone.

Edge Locations

  • Used for caching.
  • There are more Edge locations than Regions.
  • The AWS content delivery network (CDN) makes use of Edge Locations.

Source: The AWS Global Infrastructure