Domain Authorization Code (also referred to as an Auth Code, Domain's secret or an EPP Code) provides an extra level of security for the domain name registration. The authorization code is unique for each domain name and is assigned by the registrar at the time the domain name is registered. It is needed when you would like to transfer domain from one registrar to another. EPP authentication code will be required for:
.com, .net, .org, .biz, .info, .mobi, .asia, .ca, .cc, .co, .cn, .de, .in, .me, .pe, .tv, .us and .ws domain transfers.