Individual messages can be fully encrypted. But the user has to turn on that function. It's not automatic, as it is on Signal and WhatsApp. The gold standard of encryption, known as end-to-end encryption, where only the sender and person who receives the message are able to see it, is available on Telegram only when the Secret Chat function is enabled. Voice and video calls are also completely encrypted. What distinguishes the app from competitors is its use of what's known as channels: Public or private feeds of photos and videos that can be set up by one person or an organization. The channels have become popular with on-the-ground journalists, aid workers and Ukrainian President Volodymyr Zelenskyy, who broadcasts on a Telegram channel. The channels can be followed by an unlimited number of people. Unlike Facebook, Twitter and other popular social networks, there is no advertising on Telegram and the flow of information is not driven by an algorithm. The Security Service of Ukraine said in a tweet that it was able to effectively target Russian convoys near Kyiv because of messages sent to an official Telegram bot account called "STOP Russian War."
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