Optimize for conversions

The term "optimize for conversions" describes the situation when the ads expected to provide more conversions are delivered more often into the ad auction than other ads in the ad group. This option optimizes for conversions, so it takes both clickthrough rate (CTR) and conversion rate into consideration. If there isn't enough conversion data to determine which ad will provide the most conversions, ads will rotate using "Optimize for clicks" data. Although this option may result in your ad group receiving fewer clicks than the previous option, it will likely receive more conversions, which can result in an improved return on investment (ROI).

Click-through-rate CTR

CTR is the number of clicks that your ad receives divided by the number of times your ad is shown (called impressions). The click-through rate of an advertisement is defined as the number of clicks on an ad divided by the number of times the ad is shown (impressions), expressed as a percentage. For example, if a banner ad is delivered 100 times (100 impressions) and receives five click, then the click-through rate for the advertisement would be 5%.

Google Search Network

Google Search Network contains: Google Search, Google Shopping, Google Maps, Google Images, and Google Groups and search partners sites like AOL. All AdWords ads are eligible to be shown on www.google.com. Advertisers also have the option of enabling their ads to show on Google's partner networks. The "search network" includes AOL search, Ask.com, and Netscape. Like www.google.com, these search engines show AdWords ads in response to user searches, but do not affect quality score.

One of the Google+ Story

Wordpress and Google

Beginner SEO Tips

AdSense crawling further

AdSense is testing selected group of password protected websites in a program called "Site Authentication" where they allow publishers to run Google AdWords at the sites where user authentication is required. Below is part of the email explaining the new AdSense program. ”You are one of a select group of publishers that has been chosen to try out our new Site Authentication feature.
Site Authentication allows publishers to give our crawler access to login-protected content so that users can receive targeted ads. While there is no obligation for you to try out this new feature, you may find it helpful if you have pages of your site protected behind a login screen."