How does Google Analytics track session expiration?

@jamison 

Google Analytics tracks session expiration by using a combination of browser cookies and timestamps.

When a user visits a website with Google Analytics tracking code installed, a unique ID is generated for the user and stored in a browser cookie. This ID is used to associate all subsequent actions taken by the user on the website with a particular session.

A session is defined as a period of user activity on a website, which can include multiple pageviews, interactions with forms and buttons, and other types of events. Google Analytics uses a timestamp to calculate the duration of each session, and sets a default session timeout of 30 minutes.

If a user is inactive for 30 minutes or more, or if they close their browser, the session is considered to have ended, and a new session will be started the next time the user visits the website.

However, it's important to note that session expiration and timeout settings can be customized in Google Analytics. Website owners can adjust the timeout settings to better match the typical behavior of their website users and ensure accurate tracking of user behavior.