This was devised by Amazon in 2005. They called it OpenSearch (http://www.opensearch.org/ http://www.opensearch.org/) Basically it was a standard way to expose

This was devised by Amazon in 2005. They called it OpenSearch (http://www.opensearch.org/ http://www.opensearch.org/) Basically it was a standard way to expose your own search engine on your site. It made it is to programmatically search a bunch of individual sites.