Opera Software is creating a search engine to track the structure of the web, in the hopes of helping browser developers and standards bodies make it a better place.

What is MAMA?

The Metadata Analysis and Mining Application (MAMA) is a structural Web-page search engine. It trawls Web pages and returns results detailing page structures, including what HTML, CSS, and script is used on it, as well as whether the HTML validates. In this document, and the ones that link from it, you'll find data that has been pulled from MAMA so far. There is a lot of information here, but every effort has been made to keep it readable and interesting for the various types of people who might be interested in such data.

What can you get from MAMA?

The intent has always been for MAMA to provide those developing the Opera Web browser with a tool to quickly find live examples of markup and other Web page structural components. Opera believes that this tool can also be useful to other stakeholders in the standards and browser-making world. For example:
  • Browser manufacturers and others can use MAMA data on the popularity of widely used technologies to prioritize bugs and justify adding support for new technology to in-progress releases.
  • Standards bodies can use the data to measure the success and adoption rates of various technologies.
  • Web developers can use the same data to justify support of various technologies in their work.
  • It can provide real-world, practical samples of the Web developer's "art", for inspiration and instruction.


MAMA can definitely provide data on discrete issues such as "what is the 18th most popular element?" (SPAN), or "how popular is Flash?" (found in 33.5% of MAMA URLs). It can also dig deeper, by yielding regional and other data breakdowns. This allows us to discover that some countries like Germany show a decreased tendency for Flash (25% of pages), while other countries have much higher incidences (Chinese URLs in MAMA used Flash 67% of the time).