Simply put, a session is a series of user interactions on your site, beginning with the first page they visit and ending with a period of inactivity lasting longer than 30 minutes.
For example, a user finds your site in a list of Google search results and clicks through to your landing page. In FullStory, their session will begin with the landing page, and last until they have been inactive for at least 30 minutes during the session. If they revisit your site after they've been inactive on your website for more than 30 minutes, their activity will be recorded as a new, separate session.
Note: If a user is inactive and revisits your site, the session will split in the middle of a single page, after 30 minutes of inactivity.
Why do I see longer periods of inactive time in a session?
After reading our simple answer, you may be still wondering why you sometimes see longer inactive periods in a session. Read on for some more technical details:
In short, sessions organize continuous user activity over a given period of time. For a new page to be included in an existing session, the following must be true:
- The value in the fs_uid cookie must be the same as in an existing page.
- The new page's load time is within 30 minutes of the load time of the existing page.
If these two things hold true, then the new page will be attached to an existing session.
Note that the fs_uid value used for this computation is not the same as the identifier passed to
FS.identify() -- rather, it is an internal identifier used to tie pages together on a single device. Each device has its own set of cookies, and the identifier passed to
FS.identify() is used to tie the sessions recorded on different devices into a single "user" that you see in the FullStory UI. So if a single person is using your app on a desktop and phone simultaneously, they'll end up with two sessions, one for each device, but both associated with the same user in the UI.