A Session is a connection between a Visitor using a Browser and the physical system operating the Site
Why use the Concept?
It's part of the HTTP Service RidgeStar uses to implement a Referee Management Site and it's how the Server keeps track of who is at the Browser and what they're authorized to do.
How is the concept implemented?
The details are long and laborious (a function of Apache and PHP software we use to implement the Site), but essentially, you can think of each Session with the site as your connection to the server. Ergo, if you have two Browsers operating, you have two Sessions.
Comments
The Session concept also helps an Administrator to diagnose problems reported by Visitors: The Activity Log (see Administrator: Operations-Activity) collects details about each interaction with the Server by Session. It also allows Administrators to track the current usage of the Site (see Administrator: Operations-Sessions).