Google Analytics is a service offered by Google to manage your website traffic. It generates a detailed statistics about a website's traffic and traffic sources. You can see the data in realtime which includes but not restricted to how many users are currently viewing your website and are they viewing on a desktop or a mobile etc..
To set up Google Analytics Integration:
In Google Analytics, a web property is the cumulative set of pages on which a particular tracking code is installed. In the Analytics tracking code, the web property for a profile has a unique ID, which is a combination of the account ID and additional digits.
This web property ID links a web property to one or more profiles in an Analytics account. The ID can be found in the administrative section of the Analytics UI.
Go to Community>>Content>>Footer.
Paste the google analytics website tracking code in the footer.
Click on "Save Changes" button.