Are search engines case sensitive?  

Claim: Search Engines are case sensitive

Status: Generally False (there might be some such search engines).

One SEO consultant asserts in his Web site that search engines are case sensitive, and therefore the best thing to do is to write as much as possible in lower case only. This is evidently not true of major search engines. You can see for yourself, for example, that in Google there is no difference between searching for Search Engine Optimization or search engine optimization. In Yahoo! there might be a tiny difference in the number of sites retrieved, but no detectable differences in ordering of the top sites. This seems to be true even when the capitalized keyword means something different from the lowercase keyword, like Windows (Microsoft)  and windows (in your house) or Red Hat (Linux operating system) and red hat (apparel). 

Plural and singular forms may give different results. That was not the claim however.

Examples< for Keywords Windows or windows:

Google Results

Identical for both variants of the keyword

1.39 billion pages.

Top pages:

Same for both variants of keywords.

Yahoo Results

1.83 billion pages

Top pages:

Same for both capitalized and lowercase variants

Live Search MSN Results

639 million results

Top results:

Same for both capitalized and lowercase variants.

You can try the same thing with other keywords. But who are you going to believe, some silly search engine software or an "expert?"

More Search Engine Optimization Superstitions

More Links