Performance of your AdWords account can be analyzed by generating various reports available right within the Campaign tab, under the specific metric you are looking to track.
Google recently moved the reporting functions from the Report Center tab to the Campaign tab. If your account previously had created reports, check out this Google Help Center link: http://adwords.google.com/support/aw/bin/answer.py?hl=en&answer=177116.
Let's go through the definitions of the various types of reports that are available. AdWords allows you to generate the following reports:
|Keyword Reports||Information on how your keywords are performing across all campaigns or in selected campaigns.|
|Ad Reports||Information on how specific types of ads are performing, including text ads, image ads, video ads, mobile ads, and local business ads.|
|Destination URL Reports||Shows performance of destination URLs.|
|Ad Group Reports||Allows you to focus on performance of Ad Groups for one or more of your campaigns.|
|Campaign Reports||Shows statistics for each of your campaigns within an account.|
|Account-level Reports||Allows you to generate statistics for your entire account, or for a portion of your account.|
|Demographics Reports||This report is available only on the Content Network and it shows data related to demographic composition of the users who view your ads on participating publisher sites.|
|Geographic Reports||Shows performance of your ads by visitors location, as identified by the geo-tagging system.|
|Search Term Reports||Shows data related to the search queries which triggered your ads.|
|Placement Reports||This report shows performance of your ads on specific domains and URLs in the Content Network.|