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Stop Words

Stop Words are words that are so common that they have little relevance to the context of a web page. Examples would be adverbs, conjunctions and prepositions. Excluding stop words saves resources on search engines with little effect on the quality of results.

Google uses single letters and numbers as stop words as well as the following list.

about	an	and	are	as
at	be	by	for	from
how	in	is	it	of
or	that	the	this	to
was	what	when	which	who
why	will	with

Searchers can ask search engines to include stop words by using the '+' symbol before the stop word or by putting the entire search phrase in quotes but such searches are the exception rather than the norm. They are often used where the searcher knows an exact phrase from a page. A good example is the start of Hamlet's soliloquy, "To be or not to be, that is the question". The results without the stop words are very different.

Except for these specific cases stop words should be avoided in phrases that target keywords. Examples would be in anchor text, title elements and ALT (alternative) text in image links. This should not be taken to extreme, for example headings should still include stop words where it helps the readability of the content.

[1 May 2005]

Little relevance they may have but Google has recently started indexing stop words. A search for "a" now returns 4.7 Billion results, a somewhat competitive phrase.

http://www.google.com/search?hl=en&q=a&btnG=Google+Search

Stop Words

See Also