Amazon Resource Name
From Just Solve the File Format Problem
An Amazon Resource Name (ARN) is a text string used by Amazon Web Services to uniquely identify an object such as a database table, function, or access policy. They are used throughout the AWS services to associate things with one another.
They have the general format arn:partition:service:region:account-id:resource-type/resource-id, with some of these items being optional, and additional path info sometimes (which can also have wildcards), for instance arn:aws:iam::123456789012:user/Development/product_1234/*.
AWS uses some other IDs as well, including uniquely generated RequestIDs for each request submitted to a service, as well as "Trace ID" tracing headers. These are generally opaque strings with no obvious semantics.
