Exchanging text messages in real time between two or more people logged into an instant messaging (IM) service. Unlike email, messages are sent immediately, whereas email can be queued up in a ...

Offer your best promotions and get to the point, already -- or customers will unsubscribe just as quickly as they opted in to receive your instant messages.

The use of instant message, typically referred to as IM, can save a lot of time at work. Instead of walking over to someone's desk, you can send them an online chat to get a quick response.