SharePoint 2013 writes usage and health data to the logging folder and to the logging database. You can use the SharePoint Central Administration website to configure health data collection settings.

Usage reports allow you to track activity on pages through number of hits and number of unique users for a site or site collection on a daily and monthly basis.

The new Analytics Processing Component generates two reports that are based on usage event types:

• Popularity Trends shows usage event statistics for a site collection, a site, or an individual item in a library or list.
• Most Popular Items shows usage event statistics for all items in a library or list.
  

The reports are broken down per usage event type. The default usage event types are as follows:

• Views. The number of views for a single item, page or document.
  
• Recommendations Displayed. The number of times a single item, page or document was displayed as a recommendation.
  
• Recommendations Clicked. The number of times s single item, page or document was clicked when it was displayed as a recommendation.
  

If you have added any custom usage event types, these will also be displayed.