Instant messaging is a way of communicating in real time via the Internet, allowing you to chat online through either a social media website or a dedicated app, like Whatsapp or Facebook Messenger.
It can also be an instant way of sharing content - like photos, links and videos. Services like Skype also allow video and audio calls between users.However, if you're IM-ing someone you've never met, or know only online, it's a good idea to consider what you're sharing.
For information about using Instant Messaging, click here