archive about

Why nofollow is useful

There has been a lot of talking about whether rel="nofollow" is good or bad, useful or usless (check Bitflux Blog :: Why nofollow is useless )

However I think that nofollow is quite useful for a different reason than preventing spam: preventing search engine results shown on "third party" websites mislead the search engines themselves.

Here is what I mean: Take for example Most of the pages of this site display results (actually the top-10 results) returned by google for specific queries. To do this, makes use of Google Web APIs. So when google indexes one of these pages, it would increase the pagerank (or whatever ranking system a search engine is using) of a URL just because it had high enough pagerank to show up in the top 10 results...

However, using rel="nofollow" can prevent this. (I have started using nofollow in g-metrics as soon as I read about it).

Similar cases could become a big problem for search engines, as similar APIs become more popular (Google, Technorati,, Amazon/Alexa, etc...) The way I see it, similar services may oblige or encourage developers to use nofollow when presenting "their" results.