Users, sessions and hits are the foundations of digital analytics. Familiarising yourself with the hierarchy of these metrics goes a long way to helping you digest your analytics data. While this post will primarily focus on the websites, the same principles apply to mobile apps or other online points of contact.
A hit is an interaction that sends data from a website (or mobile app) to google analytics. The most common of these is page views, but there are variety of other interactions such as; virtual page views, events, social interactions, E-commerce transactions or offline uploads (such as Measurement Protocol).
A hit is the foundation of Google Analytics. Each time that data is sent from the website to Google Analytics, there can be a variety of information sent. This information is generally separated into dimensions and metrics.
From hits we move onto sessions.
Sessions, often referred to as visits, are the foundation of Google Analytics. A session, or visit, is a period in which a user is active on the website, it begins at the user’s first hit and ends after a set duration of inactivity, at the end of the day, when the user closes the browser or clears his/her cookies. Within Google Analytics the default period of inactivity is 30 minutes, however this can be changed in the admin console by selecting the following: Property Settings > Tracking > Session Settings.
While 30 minutes is sufficient for most websites, it may worth changing the session period to suit your own needs. For example you could increase the session time if you have blog articles or videos which generally last more than 30 minutes. In cases where there are periods of engagement without a hit sent to Google Analytics, it could be worth setting up additional events which trigger when the user watches X amount of video or scrolls down a certain length of the page. This would help us understand which users are actively engaged and which have left the tab open in the browser.
Users, often referred to as visitors, sit at the top of the hit, session and user pyramid. Users are defined by a unique user ID which is stored within the visitor’s cookies (so unique per browser & device). When a user enters the site for the first time, a new user ID is set in the Google Analytics cookies for that domain. In subsequent visits, the tracking code will recognise the existing cookie and attach hits to that user ID.
Traditionally Google Analytics emphasises visits over visitors due to inaccuracies of tracking individual users. However analytics and data tracking has become increasingly sophisticated and is moving towards more sophisticated user tracking solutions including cross device tracking. As such we see increasingly user-centric analysis carried out, a trend I think everyone expects to continue.
So there you have it:
A hit is an interaction that sends data from the website to Google Analytics.
A session, or visit, is a period of activity on the site, from the first hit until 30 minutes of inactivity (or another session ending action).
A user, or visitor, is a unique user id which is stored on a browser/device basis.
So a user can have multiple sessions and a session can have multiple hits.
Hope you found this helpful, and if you have any questions please feel free to reach out or leave a comment below.