Okay... going down the line...
Date - think ya know that one
Page Impressions - number of times ads have been shown on your site
Clicks - number of clicks
Page CTR - Your 'Click Through Ratio' - % -- say you show 100 ads and 1 person clicked... you then have a 1% CTR
Page eCPM - effective cost per thouand impressions. This number represents how much you get paid per/1000 ads you display.
Your earnings - What ya made

by the way.. moved topic too..