JavaScript Object Notation (JSON) (http://json.org/) is a standard machine- and human-readable information interchange format. Here's what the AZs in the us-east-1 (North Virginia) region look like, represented as JSON:

aws ec2 describe-availability-zones --output json 
{
    "AvailabilityZones": [
        {
            "State": "available",
            "ZoneName": "us-east-1a",
            "Messages": [],
            "RegionName": "us-east-1"
        },
        {
            "State": "available",
            "ZoneName": "us-east-1b",
            "Messages": [],
            "RegionName": "us-east-1"
        },
        ...
    ]
}