Transferring a domain from one company to another commonly entails the use of a unique authorization code, which different companies refer to as an EPP authentication code, a domain name password or an Auth-Info 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 registrant and is provided by the current registrar. 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 generally contains numbers and special symbols, so as to impede unauthenticated individuals from breaking it. Some domain name registrars even alter the codes of domains registered through them after a particular period of time for greater safety.