Click-through rate (CTR) is the ratio of users who click on a specific link to the number of total users who view a page, email, or advertisement. It is commonly used to measure the success of an online advertising campaign for a particular website as well as the effectiveness of email campaigns.

Click-through rates for ad campaigns vary tremendously. The very first online display ad shown for AT&T on the website HotWired in 1994, had a 44% click-through rate. Over time the overall rate users click on webpage  ... Read more »

Pay-per-click (PPC), also known as cost per click (CPC), is an internet advertising model used to direct traffic to websites, in which an advertiser pays a publisher (typically a website owner or a network of websites) when the ad is clicked.

Pay-per-click is commonly associated with first-tier search engines (such as Google AdWords and Microsoft Bing Ads). With search engines, advertisers typically bid on keyword phrases relevant to their target market. In contrast, content sites commonly charge a fixed price per click rather ... Read more »