A ‘Captcha’ is form of a Turing Test (qv) used to differentiate humans from computers programs. Their primary blog related use is to defend a blog’s comment sections from automated spam (qv). The term ‘Captcha’ a trademark of Carnegie Mellon University.

Some comment spam is overt but just as often it takes the form of innocuous remarks such as “I agree with your article!” or “Hey, great site!” in a blog’s comment section: the spammer’s ‘payload’ being in the personal details link, which takes you to a dubious (often pornographic) site. One reason comment spam is a major problem is that if readers visit the
...continue Comment Spam]]> noun. ‘Spam’ is unsolicited online messages generally of a commercial nature, usually delivered as e-mail (i.e. virtual junk mail). Comment spam however is when someone posts off-topic commercial remarks with links in a blog’s comment section.

Some comment spam is overt but just as often it takes the form of innocuous remarks such as “I agree with your article!” or “Hey, great site!” in a blog’s comment section: the spammer’s ‘payload’ being in the personal details link, which takes you to a dubious (often pornographic) site. One reason comment spam is a major problem is that if readers visit the spammer’s link(s), their site often tries to install browser hijackers, tracking cookies or other adware/malware on the duped reader’s computer. Most comment spam is entered by spambots rather than actually people.

Increasingly blogs are using technical means such as Turing tests, pre-publish moderation or registration in order to prevent spambots from polluting their comments sections with Viagra ads, online pharmacy scams and links to Russian porn sites.

Usage: “We got some useful suggestion from the commentariat today on how to deal the spammer problem.”