A bounce is recorded when a user visits only one page during a single session so the bounce rate is the percentage of sessions that resulted in just one pageview.

An entrance is the first page that a user visits during a single session.

An exit is recorded for the last page visited during a single session so the exit percentage is the percentage of pageviews where a page was the last one visited during a session.

A pageview is recorded when a user visits a page on your website.

A session is a single visit to your website and can include multiple pageviews, events and other interactions. A session ends after 30 minutes of inactivity.

A traffic medium is a general description of the traffic source and can include one of the following values:

• Email — sessions that originated from a URL in an email
• Organic — sessions that origiated from an unpaid search result
• CPC — sessions that originated from a paid search result
• Referral — sessions that origianted from another website

A traffic source is the specific location where a session originated. If the source is "none" then the user may have entered your website URL directly into a browser window or used a bookmark. "None" is also considered a default value if Google is unable to identify a source.

Unlike a normal pageview, a unique pageview is recorded only once when a user visits a page on your website during a single session. If that user visits the page several times during their session it will only get recorded as one visit.