AdWords Quality Score
Did you think that with Google AdWords the highest bidder won? Many do, but that’s not always the case. AdWords Quality Score is a score from 1 to 10 for each of your keywords as calculated by Google AdWords.

Rank Higher for Less Money
If you have a higher Quality Score for a keyword than another bidder you may obtain a higher listing result and with a lower maximum CPC bid. How is this possible? It is made possible by the way Google AdWords calculates your Quality Score.

Calculating Quality Score
The AdWords system looks at a variety of factors to measure how relevant your keyword is to your ad text as well as the search query. It is also speculated that the landing page and relevance to the ad text as well as search query may also be relevant however I have not seen that stated by Google. Quality Scores of keywords can change.

Test it out by creating a campaign and ad group with only a few related keyword phrases and then include them in a text ad. You can see the Quality Score within the AdWords editor or within the web based AdWords system, you just have to enable it.