Comment spammers are relentless. I have not posted to DaveWrites recently, but I spend time every day just deleting the comments that make it through Akismet and other spam filters.

I believe the spam-filtering service Akismet defeats most automated spam, but I suspect there is a class of low-wage human-powered spamming going on based on some internet marketer's idea of link building.

The reason some people post short comments like "Nice job. Keep up good work." or "Good information, thanks for the post!" is because the comment form gives them the opportunity to link to another web site. That link becomes a part of my blog because it is published with the comment. This a legitmate way to build connections between bloggers. When I comment on someone else's blog that has much more traffic than mine, I hope that people will check out my site to see what else I'm writing.

But the reason spammers comment on blogs is to improve search engine rankings. Links from blogs to web sites increase the ranking of those sites, because search engines believe sites with many inbound links are more authoritative and creditable. So a business might pay a marketing firm to go out and comment on all the blogs they can find. Then, they report back to the company: "we've generated 100 inbound links for you!"

The sad thing about such an approach--apart from my annoyance at these bozos--is that it is a fraudulent scam on the companies who are paying the "internet marketing firm." Read Google's opinion of comment spam on their blog. The message from Google is clear:

• it does not work; they will detect it and ignore it
• it can hurt you; they will penalize sites that use it

My simplistic description of how inbound links affect search engine ranking is NOT very accurate. Google has spent the last decade refining their algorithms for ranking sites. So it is not as simple as getting some links.

None of this is new. I've been deleting comments like this for years, and I try to avoid even thinking about it because it is a distraction from working on something that might actually generate some revenue for my business. But I think all bloggers should review Google's recommendations on how to fight comment spam just to make sure they are not just hitting the snooze button every day for years. Let's walk through Google's recommendations with some real world practical commentary...

I think the CAPTCHA and Akismet approaches are the most worthwhile to pursue. Many of us set up our sites years ago and it's worth a review of the technologies available to update our sites to make sure we are minimizing the amount of predictible spam, then, just delete those bogus comments that slip through.

This post turned into more than a few minutes diversion...feel free to submit your own comments and links to practical ways to fight spam. I'm sure this post will itself create a moderation challenge for me. :)