What type of Internet monitoring technique records information about a customer during a web surfing session, such as what websites were visited and how long the visit was, or what ads were viewed and what was purchased?

Click-stream is the type of monitoring technique used for web surfing sessions. Browsers maintain cookies for the websites being visited from a machine (computer, mobile ...), this technique gathers the surfing data from here. Moreover a timer is set for every web page clicked to calculate the amount of time the user stayed on it. Purchasing done by the user is also stored in the cookies section as well.