I have justed sign up for adsense and do not know about adsense deeply. Can any one tell me about Page impression what is this and page ctr?
You can click this link https://www.google.com/adsense/support/bin/answer.py?hl=en&answer=32744 CTR is a way of measuring the success of an online advertising campaign.
Page Impression is how many times your ad is viewed. If you have lots of pages but high bounce rate, you'll probably be far from your maximum potential. So keep your site interesting and invite the user to browse around more than just the front page via internal links. CTR is the amount of clicks you get vs. the number of impressions. This is related to the quality of your traffic. If you get lots of search engine traffic (valuable) then they are targetted and looking for solutions even from paid advertisers. Repeat visitors or stumbleupon are low quality for advertising and are generally ad blind.