As details emerged after ISIS' coordinated, deadly attacks on Paris and Beirut last week, one name stood out in conversations about communications channels: Telegram. ISIS operatives use Telegram and other encrypted messaging services to communicate -- a fact that was apparently news to Telegram. In response, this week the company blocked 78 ISIS-related channels in 12 languages. "We were disturbed to learn that Telegram's public channels were being used by ISIS to spread their propaganda," the company writes. Telegram found and blocked the channels based on user-submitted reports.