Sessions, Users and Page Views are three metrics used by Google Analytics to measure the traffic to your website. The purpose of this article is to make you understand the difference between the three. A perfect understanding of these three terms requires that one understands some basics related to cookies and the functioning of Google Analytics.

Cookies

Cookies are pieces of data stored on the visitor’s browser which can be used for a variety of purposes like storing his preferences, identifying him as a person separate from other visitors etc. A single website can store any number of cookies on a visitor’s browser. A cookie is associated with a website and each time any page from that website is requested, all the cookies created by that website are sent along with that request. Cookies also have an expiration date that is set by the code from the website itself.

Users

Google Analytics is based on Javascript which uses cookies to keep track of visitors. When a person, for the first time, visits a website having Google Analytics installed, an ID for that user is created and is stored on his browser as a cookie. This ID is used to uniquely identify that visitor or to be more specific it identifies that browser. If the same visitor visits that website from a different browser or a different computer, he will be regarded as a new user and will be given a new ID. But it is safe to assume that a person always uses the same computer and browser to surf websites. Even if this is not true for all users, the effect on the stats wouldn’t be too high.

The duration of this cookie which identifies a visitor is two years. Each time, the visitor visits any page on your website, the expiration date will be reset to two years. For example, consider that a new user has visited a page on 1st Jan, 2014. A new cookie containing his visitor ID will be created and its expiration date will be set to 1st Jan, 2016. If he visits your page on 1st Jan, 2015, the expiration date will be refreshed and set to 1st Jan, 2017. If he doesn’t visit your page again before 1st Jan, 2017, the cookie will be deleted. So, if he visits your website for the third time on 1st Jan, 2018, there will be no cookie containing his visitor ID and so, he will be regarded as a new user.

The Users metric shown on Google Analytics corresponds to this visitor ID cookie. The number of users in a selected time range is the number of people with unique visitors IDs who have opened your site in the selected time range.

To make it simpler, users is the number of people who have visited your site. Even if one of them has visited your site multiple times, he will be counted as single user.

Sessions

A second cookie used by Google Analytics is the session cookie which has an expiration of 30 minutes. The working of this cookie is similar to the working of visitor ID cookie. If a person visiting your site doesn’t already have a session cookie, then a new session cookie will be created. If he already has one, then the expiration time of that will be reset to 30 minutes.

The number of sessions in the selected time range is the number of requests with unique session Ids.

Now, let us try to understand the significance of sessions. Session is an estimate of the number of times people have opened your site and have performed some transaction. For example, let us say that the site we are considering is an email service like Gmail. If a person checks his mail thrice every day, then he will be contributing three to the number of sessions every day. Some of his sessions may be shorter (1-2 min) and some of them may be longer (1-2 hrs.). Remember that the duration of a session cookie is 30 minutes and the expiration will be refreshed every time some page is opened. So, even if a person surfs yours site for 10 hours and opens atleast one page every 29 minutes, he will be contributing to the number of sessions by only one.

Page Views

The metric page views is straightforward to understand. It is the total number of times any page of your site has been viewed. If a single person views a page multiple times, then multiple views will be counted for calculating page views.