Session,What are they and how do they work?
The term session refers to the duration of an event. Its temporary nature is undefined and in each case it refers to a different period, since there are very short sessions, of a few minutes or several hours. Normally its duration does not exceed 24 hours a day.
By default in Google Analytics a session is defined as the period of time during which users interact with the website having an inactivity of less than 30 minutes. After 30 minutes of inactivity any page viewed by that user will be treated as a new session. Those users who leave a website and return to it before 30 minutes pass will be counted as part of the original session. If desired, the tracking code can be modified to extend or reduce the minimum session end time.
One of the limitations of web pages is that each web page is a separate document. That means that two PHP programs cannot, in principle, share information.
In principle, the only way to send information from one page to another is through a form and it is the information that the user has entered in that form. At the most we can send additional information through hidden controls (as discussed in the section on hidden controls of the Miscellaneous lesson), or we can “imitate” a form by redirecting to another page by sending information at the address (as discussed in the lesson on headers), but this cannot be considered as sharing information, since the page that receives the information cannot know if the information has been manipulated by the road or who sends it.
By sharing information we are referring to using common variables in different programs, without the information leaving the server.