A click-through rate (CTR) is the rate at which clicks are measured for a specific ad. Click-throughs are generally counted ‘only’ when a surfer actually clicks on your ad (banner ads, text ads etc.).

The rate of click-throughs are gauged by counting how many times an ad is clicked for every 100 times your ad is shown. In other words, if you have placed an ad on Google’s Content Network you might have notice that your ad had 100 impressions (has been shown 100 times) and you may have recieved 1 visit to your site from web surfers that have clicked on your banner. This would give you a 1% click-through rate (1 click for every 100 times you banner is shown).

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