Private message

Long a function present on IRCs and Internet forums, and the standard means in email,[1] private channels for PMs have also been prevalent features on instant messaging (IM) and on social media networks.

Peter Drucker published an article centering on the theme that the computer is to the Information Revolution what the railroad was to the Industrial Revolution; railroads unified travel between the east and west coast of the United States, whereas computers unified communication across the entire globe.

[citation needed][citation needed] The first email system able to send mail between people using different host computers was launched via the ARPANET in 1971, and it revolutionized personal messaging by enabling users to send electronic messages to distant recipients.

[citation needed] Today, private messaging is a staple of established social media platforms and more recently-developed applications.

In January 2014, Matthew Campbell and Michael Hurley filed a class-action lawsuit against Facebook for breaching the Electronic Communications Privacy Act.