Transferring a domain name from one company to another typically involves the use of a unique domain authorization code, which different registrar companies refer to as an EPP key, a domain password or an AuthInfo code. This code can be used as a protection measure against unapproved transfers 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 present domain registrar company. It must be given to the new registrar company because the transfer process cannot be initiated without it. The code is case-sensitive and generally contains numbers and special characters, so as to prevent unauthorized persons from hijacking it. Some companies even alter the codes of domains registered through them every now and then for even better security.