Sites are generally created using either HTML or Adobe Flash.Flash is a proprietary format that became a de facto standard, once supported by all major browsers with the aid of a browser extension.Certified Site Metrics are metrics that are directly-measured from the website instead of estimated.The website owner has installed an Alexa Certify Code on the pages of their site and chosen to show the metrics publicly.The W3C started Amaya in 1996 to showcase Web technologies in a fully featured Web client.This was to provide a framework that integrated lots of W3C technologies in a single, consistent environment.Although they are more flexible than online builders, they are often expensive.However, some open source website builders may be downloaded free of charge or by "freemium" license model.
Open source tools were typically developed to the standards, and made fewer exceptions for the then-dominant Internet Explorer's deviations from the standards.
If a site has Certified Metrics instead of estimated, that means its owner has installed code allowing us to directly measure their traffic.
These metrics have a greater level of accuracy, no matter what the ranking.
Daily Pageviews per Visitor Estimated daily unique pageviews per visitor on the site.
Daily Time on Site Estimated daily time on site (mm:ss) per visitor to the site.