Amazon Web Services (AWS) has many data centre's in many continents and countries all over the world. AWS has two key grouping methods of these data centres: regions and availability zones.
Sidebar: Click here to read up more on regions and availability zones or click here or click here. Included in these references is also information about the DNS endpoints for services that are therefore IP address agnostic.
It can be very handy to either reference the IP address or subnet of a particular service in say a proxy server to streamline connectivity. This is a good practice to avoid unnecessary latency via proxy authentication requests.
Below is an output of Amazon Web Services IP address and subnet details split into the key categories as listed by AWS via thier publishing of information through the IP address JSON file available here.
Sidebar: If you'd like more details about the JSON file click here.