Google adds a ‘no-follow’ tag

I haven’t seen this mentioned in many places at all, perhaps everyone follows the Google blog?

Google has added an unofficial rel attribute value to the a tag that their indexer will know how to understand: rel="nofollow". Using this tag as part of a link will say to Google "I am linking to this page, but that does not mean that I think its rank in your search engine should be increased."

Why are they doing this? Well, if you haven’t heard about comment spam this might not make sense to you, but many popular weblogs and wikis are continually hit with people leaving comments like "get your discount viagra here" with a link. They sometimes get hit so much their bandwidth limit is reached or their server crashes under the load.

People occasionally ask "Does this really work? Sure it appears on the page, but it seems even less effective than email spam. People from my rightist libertarian feminist discussion board have Viagra suppliers already! They will ignore these dumb comments you leave." And that’s all very well, until one day you get hit with 15000 spam comments in a single day and have to turn comments off.

The answer to "does it work?" is suspected to be: it works, but not like you think. While they probably would think it’s a bonus if your weblog readers clicked, you know who they really want to ‘click’? Google. Why? Because Google counts the number of links to a website as a measure of how ‘good’ that website is as a search result. If they can add their link to enough pages (including yours, through your comment form), then zooooom up the search results they go.

Anyway, this tag is Google’s attempt at an answer. By marking URLs provided by commenters as no-follow, you can say "Dear Google, I don’t trust this link, so neither should you. For popularity purposes, this link never happened, OK?" Ideally, it will remove the spammer’s motivation for posting on weblogs. (The problem of wikis is much harder, since all the content is user created, it’s not really possible to mark out bits of it as ‘Google good’ and ‘Google bad’.)