Transferring a domain name from one company to another commonly involves the use of a special domain authorization code, which different companies call an EPP authorization code, a domain password or an Auth code. This code can be used as a protection mechanism against unsolicited transfer attempts with all gTLD and with most ccTLD extensions. It can be obtained only by the domain name owner and is issued by the current registrar. It must be given to the new domain name registrar company because the transfer cannot be initiated without it. The code is case-sensitive and normally contains numbers and special symbols, so as to impede unauthenticated people from deciphering it. Some domain registrars even change the codes of domain names registered through them after a certain interval of time for even better security.