I believe it is a internal ID assignment to the various realms. I guess datamining is one way to retrieve this list. Haven't found an easier method just yet.
*Edit* You can find, at least the public available realms, over at character transfer. The page HTML contains javascript data on realm names and internal ID's. So far this is the easiest way to extract the list of realms and their IDs:
- https://eu.battle.net/account/manage...ct-select.html
- Select account with at least one character.
- Select character.
- Run the following script on the page to get the realm list in return.
Code:
var r=RealmSelector;if(r){var d=[];for(var i=0;i<RealmSelector.realmID.length;i++){d[i]=[parseInt(r.realmID[i]),r.realmName[i].trim(),r.realmType[i].trim(),r.realmLocale[i].trim()]}console.log(JSON.stringify(d))}else{console.log("Can't find RealmSelector object.")}
The script will simply read from the RealmSelector object on the page and extract realmID, realmName, realmType and realmLocale, store it in an array and return that array in the console as JSON for easy copy-paste.
The downside is this requires you to login, do some actions then finally get the list. It's also limited to your region, so you need another account from other regions if you want to copy their realm information. Mine is EU and this is what the script above dumped:
http://pastebin.com/rqTWCPWj