Transferring a domain from one company to another generally involves the use of a special domain authorization code, which different registrar companies call an EPP authorization code, a domain name password or an Auth code. This code can be used as a protection measure against unsolicited transfers with all generic and with most country-code extensions. It can be obtained only by the domain name registrant and is issued by the present registrar company. It must be given to the new registrar company because the transfer cannot be initiated without it. The code is case-sensitive and usually comprises of numbers and special symbols, so as to prevent unauthorized individuals from cracking it. Some domain registrars even change the codes of domains registered through them periodically for greater safety.