Transferring a domain name from one company to another normally entails the use of a unique authorization code, which different registrar companies call an EPP authentication code, a domain name password or an Auth-Info code. This code can be used as a security mechanism against unauthorized transfers with all gTLD and with most ccTLD extensions. It can be obtained only by the domain owner and is issued by the current domain name registrar company. It must be given to the new domain registrar company because the transfer procedure cannot be started without it. The code is case-sensitive and ordinarily comprises of numbers and special characters, so as to hinder unauthenticated people from cracking it. Some registrar companies even change the codes of domains registered through them after a certain amount of time for greater security.