Transferring a domain from one company to another ordinarily entails the use of a special domain name authorization code, which different registrar companies call an EPP authentication code, a domain password or an Auth-Info code. This code can be used as a protection measure against unapproved transfer attempts with all gTLD and with most ccTLD extensions. It can be obtained only by the domain registrant and is provided by the present domain registrar company. It must be given to the new registrar because the transfer procedure cannot be started without it. The code is case-sensitive and usually includes digits and special characters, so as to impede unauthorized people from cracking it. Some registrar companies even alter the codes of domain names registered through them periodically for even greater security.