Spam in blogs (also called simply blog spam or comment spam) is a form of spamdexing. It is done by automatically posting random comments or promoting commercial services to blogs, wikis, guestbooks, or other publicly accessible online discussion boards. Any web application that accepts and displays hyperlinks submitted by visitors may be a target.

Adding links that point to the spammer's web site artificially increases the site's search engine ranking. An increased ranking often results in the spammer's commercial site being listed ahead of other sites for certain searches, increasing the number of potential visitors and paying customers.

History

This type of spam originally appeared in internet guestbooks, where spammers repeatedly fill a guestbook with links to their own site and no relevant comment, to increase search engine rankings. If an actual comment is given it is often just "cool page", "nice website", or keywords of the spammed link.

In 2003, spammers began to take advantage of the open nature of comments in the blogging software like Movable Type by repeatedly placing comments to various blog posts that provided nothing more than a link to the spammer's commercial web site. Jay Allen created a free plugin, called MT-BlackList, for the Movable Type weblog tool (versions prior to 3.2) that attempted to alleviate this problem. Many blogging packages now have methods of preventing or reducing the effect of blog spam, although spammers have developed tools to circumvent them. Many spammers use special blog spamming tools like Trackback Submitter to bypass comment spam protection on popular blogging systems like Movable Type, Wordpress, and others.

Possible solutions

From Wikipedia under the GNU Free Documentation License
Sun Jan 31 06:26:47 2010

How can you prevent comment spam when you own a website?
Q. Which is the best way, please this is urgent, spammers are taking over the site
Asked by teacher's pet - Fri Jun 22 21:11:07 2007 - - 2 Answers - 0 Comments

A. Hi, First, if you have your own website the spammers are either flooding you with emails to your website domain name, or you have a web page form, like a Contact Us page, that is not secure and they have hijacked that form. There are a number of things you can do. If the spam is coming to you for a legitimate email address from your website, you should be able to access your website's Control Panel and change your password, even put quotas and limits on specific email accounts including turning on spam protectors. You can tell if the spam is coming to you from one of your own email accounts, for example it will have your domain name in it (name@yourwebsite.com) unless the spam is spoofed to look like that. Do change your password… [cont.]
Answered by desertcities - Fri Jun 22 21:22:40 2007

How can i mark my comments on youtube to spam?
Q. Does someone have to mark the comment as spam, or can i do it my self?
Asked by michaelkioken - Wed Aug 12 13:38:38 2009 - - 1 Answers - 0 Comments

A. You can do it yourself, when you're logged in. Just go to the video with the comment and press the "mark as spam"-button on the right of the comment. Good Luck.
Answered by Job - Thu Aug 13 11:22:12 2009

Does it help or harm your site's SEO if you comment (not spam, but comment) on blogs?
Q. I have been given a list of over 2000 PR4+ blogs. Will it help my site's search engine optimization if I read the blogs and comment on the post with a signature? Such as: Comment: Blah blah blah -my name www.mysite.com Will that help the search engines see me and appear in rankings higher? I won't spam and say irrelevent stuff like, "Hey everybody, check out my site! www.mysite.com," but I would comment on what I think about the article and then sign my name and website. You can find several good ones on eBay, just make sure to check their feedback before you buy and see what other buyers said about the product.
Asked by Ian - Sun Feb 3 01:20:25 2008 - - 4 Answers - 0 Comments

A. Ian, this is one of the most relevant ways to increase your inbound link numbers while helping your rankings with your website. Do your comment signature like this. local seo services - Terry Reeves Or whatever you would like to rank for. I posted this signature in blogs for several days and I now rank on the first page of Google for local seo services. It is one of the methods I use when ranking clients sites as well. Google now considers the hyphen ( -) a word or phrase separator. So I also rank very well for my own name. This is not the best type of inbound targeted link you can get, but they are very effective with rankings and PageRank at this time. Also. Do not concern yourself with follow blogs over nofollow blogs. I have… [cont.]
Answered by Terry R - Sun Feb 3 17:12:37 2008

From Yahoo Answer Search: "Comment Spam"
Sun Jan 31 06:27:11 2010

See also:

Custom search only Comment Spam sites:

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Fri Jan 22 15:20:35 2010
30 Black Hat SEO Techniques You Can Use Ethically - SEOptimise (blog)
news.google.com
30 Black Hat SEO Techniques You Can Use Ethically

SEOptimise (blog)

Then let spammers comment spam it or even add posts (via TDO Mini Forms). Last but not least parse the comments for your keyword and outgoing links. ...



and more »
NCWV Sports Scores for Jan. 29 - WOWK
news.google.com
NCWV Sports Scores for Jan. 29

WOWK

... required to allow WOWK-TV to monitor comments and track users posting inappropriate comments . WOWK-TV does not use these for any type of SPAM operation. ...



and more »
Experimental Free Handicap ranks 2009 2-year-olds - San Luis Obispo Tribune
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Experimental Free Handicap ranks 2009 2-year-olds

San Luis Obispo Tribune

Don't repeat the same comment over and over. We heard you the first time. Do not use the commenting system for advertising. That's spam and it isn't allowed ...



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From Google News Search: "Comment Spam"
Sun Jan 31 06:25:56 2010

gestbook spam png
chedong.com
gestbook spam png
456px x 985px | 34.00kB

[source page]

groups beta google com comment spam MT Google Groups

spam comment jpg
seo.mhvt.net
spam comment jpg
868px x 943px | 209.60kB

[source page]

Screenshot 01 Source MacHouse

spam jpg
tigertwotiger.co.uk
spam jpg
375px x 500px | 223.70kB

[source page]

The funniest comment spam yet February 18th 2009 by Nancy I just had to blog this We received some comment spam recently on the blog which had us in stitches It made us laugh so much that I have kept a copy of it and when we need to lighten up the

From Yahoo Image Search: "Comment Spam"
Sun Jan 31 06:24:21 2010

Etsy :: The Storque :: How-To :: Handmade Comments : How Not to ...
etsy.com
Etsy :: The Storque :: How-To :: Handmade Comments : How Not to ...

Vanessa

ue, 26 Jan 2010 22:19:00 GM

You're at a gallery opening, discussing the paintings with the artists and other attendees. Someone bursts into the room shouting, "I make paintings too!" and tosses a fistful of flyers on the floor and leaves.

Avoiding Wiki- Spam for SEO | SEO Consult - Certified Search Engine ...
seoconsult.co.uk
Avoiding Wiki- Spam for SEO | SEO Consult - Certified Search Engine ...

Jon

ue, 19 Jan 2010 09:08:08 GM

Blog . comment spam. has been around for a while, and most businesses are smart enough to avoid it. Blog . comment spam. began with the obvious spam comments, which featured a blatant advertisement that had no relation to the blog post it was ...

AlSki.net | Comment Spam
alski.net
AlSki.net | Comment Spam

alski

ue, 22 Dec 2009 11:49:00 GM

Well I admit defeat. I have approx 500 . comments. to go through and most likely none are real . comments. . So I'm shutting down my . comments. entirely for the christmas break. Have a nice Christmas (unless you are a . spam. bot) ...

From Google Blog Search: "Comment Spam"
Sun Jan 31 06:25:57 2010