Just like the sea of content on the web, there is immense mix and mash of technologies that go into creating web sites. HTML, CSS, XHTML and their different versions to name a few.
Opera is planning to make available a search engine that indexes this structural information.
An excerpt from PC Advisor :
Metadata Analysis and Mining Application (MAMA) grew out of tests Opera routinely does to make sure its own browser software products work well with existing web pages that use the most commonly used web site-creation technology, he said.
“We realised internally that we needed to be able to find lots of live sites out there that used certain technologies in certain combination so we could test our browser on them,”
The engine would be made available towards the end of the year on an invite only basis. Web developers can use it for information on how best to implement ideas. At the same time the engine would provide information on how well sites confirm to the W3C specifications and what changes could be made to the current specs based on implemented practices.