Transferring a domain name from one company to another ordinarily involves the use of a special domain authorization code, which different registrar companies call an EPP authentication code, a domain password or an AuthInfo code. This code can be used as a security mechanism against unauthorized transfer attempts with all gTLD and with most ccTLD extensions. It can be obtained only by the owner of the particular domain and is issued by the current domain registrar company. It must be given to the new registrar because the transfer process cannot be initiated without it. The code is case-sensitive and usually comprises of digits and special symbols, so as to hinder unauthorized people from hijacking it. Some companies even change the codes of domains registered through them after a certain interval of time for even better safety.
