What is Site Meter tracking exactly?

Site Meter tracks page views and visits. You may also have heard the term "hits". When someone comes to your site, they generate a "hit" for every piece of content that is sent to their computer. Viewing a single web site page would generate one hit for the page and one hit for every individual graphics file that was on the page. A single page could easily generate a dozen or more hits. When you are browsing a site, every time you follow a link, it is treated as a single "page view". Site Meter defines a "visit" as a series of page views by one person with no more than 30 minutes in between page views.
[SOURCE: SITEMeter Home]
MooPig Wisdom Last Week
(s31PatrickDarnell)

-- Site Summary ---
Visits

Total ........................ 9,503
Average per Day ................. 32
Average Visit Length .......... 4:28
This Week ...................... 227

Page Views

Total ....................... 14,850
Average per Day ................. 49
Average per Visit .............. 1.5
This Week ...................... 344