Telegram (informally abbreviated as TG or Telegraph) is cross-platform instant messaging software whose client side is free and open source software, but whose server side is proprietary software.

Users can not only send messages, pictures and recordings via Telegram, but also enjoy a variety of security options. It uses end-to-end encryption, so all chat content (including attachments) is not transmitted through the Telegram server and therefore cannot be seen by third parties. It also offers a "burn after reading" timer, which means that private messages will disappear after a certain amount of time.

The company, founded in Berlin with just 45 employees, is now operating worldwide. It has been a huge success in Iran, with over 2 million downloads, and has been well received in Ukraine, Russia, Saudi Arabia, the United States, Brazil, India and other countries.

Prior to founding Telegram, Pavel Durov was the CEO of VK (formerly VKontakte), Russia's largest social networking site, where he was forced to move to the United States after losing control of his former company. Subsequently, he announced that he had created the Telegram application for his brother.

Compared with other similar apps in the market, Telegram has three main features: "high privacy", "rich cross-platform support" and "free and great development flexibility". The emphasis of communication software is always on the convenience of communication between people, because even if you register and use it happily, but there are no friends to talk to, then the app itself, even if it is perfect, will lose its original meaning. Some people think that Telegram is the most perfect communication app of our time, not only is it complete and open, but it is also free and free, and at the same time it is highly secure, which has won the favor of internet users all over the world. For example, Telegram has a strict privacy policy, "end-to-end" message encryption from the beginning of the software design, and an exclusive network transmission protocol, MTProto, which makes any communication records almost impossible to be broken by external forces. in the cloud. In other words, Telegram users don't need to think about "how to backup" or "manually backup" at all.