What is IM?
IM stands for Instant Message, a message sent over the internet via any number of real-time chat applications. IM differs from other forms of online communication like email and forums in that conversations occur in real time and are usually, but not always, private.
How does IM work?
The most popular instant messaging apps today are for mobile devices, including Facebook Messenger, WhatsApp, WeChat, Telegram, Viber, and Line. Instant messaging apps are primarily text-based but have evolved to include voice, video, images, links, stickers, and more.