Visual Website Optimizer is an Easy to use A/B testing tool that allows marketing professionals to create different versions of their websites and landing pages using a point-and-click editor and then see which version produces maximum conversion rate or sales.
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The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical", or "preferred".