Conversion Rate is the ratio of number of website visitors to those who have successfully been converted into potential clients. Your visitors and explorers need to show eagerness to become your customers in order for your Conversion Rate to increase. A sale through the website, a membership registration, a completed contact form or a download, all qualify as successful conversions. Conversion Rate Optimization is aimed at increasing this very conversion ratio. It uses the existing traffic to increase the client base as opposed to the primitive method of just increasing the internet traffic.