Prefixing a text with the letter "D," the letter "M," or "DM," followed by a username is how you start a direct message via SMS. This behavior eventually carried over to Twitter's APIs as well ...

in a new section of Twitter's Help Center, the company explains that the goal of DM encryption should be "if someone puts a gun to our heads, we still can’t access your messages." Twitter then ...

Matt Binder: X, formerly Twitter, is blocking users from posting a "Signal.me" link through DM ... page. When trying to post ...