Sourced From SearchDayThese days, web search is dominated by giants, and it’s rare to see the emergence of a new potentially world-class search engine. Meet Exalead, a powerful search tool with features not offered by the major search engines.

Exalead is a fairly new search engine from France, introduced in October 2004 and still officially in beta. Having passed the one-billion page mark in 2005, it’s still 1/8th the size of Google or Yahoo, but what’s a few billion pages among friends? Actually, after a certain point, size really doesn’t matter. The key factors in evaluating a search engine should include timeliness, ability to handle ambiguity, and plenty of power search tools. Exalead does a great job, at least on two of these three criteria.

When you first get to the Exalead site, you’ll see a stylishly minimalist page. But click through to the advanced search page to appreciate the full scope of Exalead’s search features.

Exalead provides a number of search tools that you don’t always find elsewhere.

Want to use a fuzzy query? Use the option to specify that retrieved sites “preferably contain” all the terms you are searching for, in addition to “must contain” and “must not contain”. You can also do this with the OPT operator, to indicate which specific words are “optional”.

Exalead is one of the only search engines to allow proximity searching(!), in which the words you search must be within 16 words of each other. (No, you can’t tweak the number of intervening words.)

It also offers truncation, and this isn’t just the word stemming that many search engines employ behind the scenes (a search for “pencil” will also retrieve “pencils”) but true truncation, where you can search for “librar” and retrieve library, libraries, librarian, librarianship, and so on.

If you have trouble spelling, you’ll love the phonetic spelling and approximate spelling options, through which you can search for a word, even if you aren’t sure of the spelling or if the word is frequently misspelled. Think “Arnold Schwarzenegger” for example.

Exalead also lets you use “Regular Expressions,” in which you can search for documents with words that match a certain pattern. Imagine, for example, that you’re doing a crossword puzzle and have a word of 6 letters, of which the second is T and the sixth is C. By searching /.t…c/, you will retrieve sites with the word ATOMIC, perhaps the right word for your puzzle.

One gripe I have is that there is an option to limit your search by country but, unfortunately, this only searches by two-letter top level domain (e.g., .uk, .jp). This means that, for example, if you limit your search to Australian sites and search for Australian biotech associations, you won’t retrieve — a major biotech association in Australia — because it does not have .au as its top level domain.

In addition to search power, Exalead has a rich search-results screen. Along with the usual display of search pages and snippets, each entry includes an image of the retrieved page. There is also a column along the left that displays relevant entries from the Open Directory Project, along with tools to select “related terms”, to limit your search by document type, and to narrow the search by location (and, interestingly, this doesn’t use the two-letter top level domain limit, but instead retrieves only pages from the Open Directory Project that have been categorized under that country.)

My one real objection to Exalead—and it’s a big issue—is that it appears that Exalead has not updated its index since the beginning of 2005. One of its advanced search features lets you limit your search by the date a file was last modified (note that you need to use the European format of dd/mm/yyyy), but repeated tests turned up no results from 2005. Yes, Exalead is in beta, and that sometimes means there are glitches, but a delay in over four months in updating the index is troubling.

That will change, and soon, says Francois Bourdoncle, Exalead’s CEO. The company is in the process of completely refreshing their index. However, until Exalead gets its updating schedule back on track, use this search engine to find older material and/or to verify spelling, identify alternative meanings, and identify authoritative material from sites that have a track record.