opsdo has two goals - to allow people to search many information sources which mainstream search engines do not cover well and to allow people to search groups of such sources -- e.g. RottenTomatoes, IMDb and Amazon.
OpenSearch is a set of simple formats for the sharing of search results. Any website that has a search feature can make their results available in OpenSearch™ format. Other tools can then read those search results. For example, here is an aggregator tha
RefSeek (rĕf-sēk) is a web search engine for students and researchers. RefSeek aims to make academic information easily accessible to everyone. RefSeek searches more than one billion documents, including web pages, books, encyclopedias, journals, and newspapers.
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