Metrics are quantitative information about visitor activity, such as Views, Click-Throughs, Reloads, Average Time spent, Units, Orders, and Revenue.
Metrics are the foundation of reports and help you view and understand data relationships. They let you perform side-by-side comparisons of different data sets about your website.
Page View: One Web page load in a user's browser (one execution of the Reports & Analytics code).
Visit: Any number of page views when visitor comes to your site. A visit ends after 30 minutes of inactivity.
Unique Visitor: A person visiting your site for the first time during a given time frame, such as Hour, Day, Week, Month, Quarter or year. (This also includes Unique Visitors for any time frame.)
These show data about success events, such as purchases, downloads, or any other action that you want users to take on your website.
Analytics provides support for tracking a number of video metrics, including total views, time spent, and completion rates.
You can measure your brand's presence on the social web. Social metrics work with Analytics standard metrics. By combining these with calculated metrics, you can view a report that shows how often a product is mentioned, gauge product sentiment, and see how Social metrics correlate with Analytics key performance indicators.
Calculated metrics enable you to combine metrics to create mathematical operations that are used as new metrics. These metrics can be created for a report to which you add metrics. Administrators can create calculated metrics for all users of a report suite.
See Metrics in Analytics Help and Reference for metric definitions.