Postal, telegraph and telephone service
（重定向自Postal Telegraph and Telephone）
A postal, telegraph, and telephone service (or PTT) is a government agency responsible for postal mail, telegraph, and telephone services. Such monopolies existed in many countries, though not in North America or Japan. Many PTTs have been partially or completely privatized in recent years. In some of those privatizations, the PTT was renamed completely, whereas in others, the name of the privatized corporation has been only slightly modified, such as PT Telkom in Indonesia.