What is Heartbeat?

The simplest answer is when a user is completely idle the system receives a continuous heartbeat for 3 hours which maintains the users session. After 3 hours the heartbeat stops and the system prompts the user to keep their session open (which would allow them to save their data)

This prompt stays open for another 30 minutes at which time the session will expire (and all unsaved data will be lost)
The Heartbeat feature is not activated if a user clicks "Remember Me" when they sign-in.

Note: if the user simply scrolls the page or does anything that notifies the system that someone is alive at the other end, the heartbeat session is reset!