Captcha’s vs. Autobots

July 21, 2005

Tunog Transformers ah…

Tired of spam, eh…

Every time na nagsa-signup kayo for e-mail or another related service, minsan ay nire-require kayo na basahin ang isang autogenerated image of a distorted word or number, and then kailangan nyo pa itong i-recognize at i-type ang word or number na yon sa isang text field bago kayo maka-proceed. The image usually looks like this:

It’s called Captcha.

CAPTCHA stands for “Completely Automated Public Turing Test To Tell Computers and Humans Apart”. Ayan ha, may pang-trivia na kayo sa classmates at barkada nyo. ;-P

As the meaning behind the acronym tells us, it’s a mechanism that attempts to distinguish humans from computers. Spammers are usually automated in nature; they are usually computer programs (”bots”) created by bad hackers, programs that mercilessly flood your e-mail, tagboard, trackbacks and chatrooms with hundreds of online casino and porn stuff. (FYI: “Bad hackers” is not redundant. Not all hackers are bad.) These programs imitate human interactions (an exercise in artificial intelligence) such that their interactions are virtually indistinguishable from the equivalent human interactions in the victim system’s point of view, such as your e-mail’s server, your blog’s engine, or even you yourself. (E.g., you can’t tell whether a human or a bot sent you that annoying e-mail.)

And that’s where a solution is needed that can separate the goats from the sheep, the weeds from the wheat, and the bots from the humans. That’s where Captcha’s come in.

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