Directories are NOT Search Engines. They are directories, approaching phonebooks, that have been categorizing the Internet for time of life. Of the supreme prominent directories on the Internet the top one is DMOZ but there are too a few 200 second-rate notable ones.
Some of the Search Engines use the book of facts tabular array in their Search Results. Look Smart is one, AOL is another. Yahoo used to use the DMOZ calendar as part of the pack of its investigate grades. Many mediocre known, but active, search engines use directories as the cause for providing facts for all of their searches.