What is a CAPTCHA? In short, a CAPTCHA (hereinafter referred to as captcha, because I hate typing words in caps!), is a device which allows you to eliminate or at least reduce spam on forms that are available to the public to post to, eg. comment forms on blogs, quick contact forms on your website, etc. Captcha stands for “Completely Automated Public Turing test to tell Computers and Humans Apart”, quite a mouthful isn’t it? Essentially, captchas use an image that is usually heavily distorted in order to fool automated systems from posting to your forms as mentioned above. These automated systems, otherwise known as SpamBots, are not able to read the text in the image and fill out the text field which humans are required to do, and therefore their comment or email is never submitted.
So why is having a good strong captcha important? Well, so these spambots don’t render the comments section on your blog useless with links for viagra or links to malware sites, or worse yet, sites which contain less than work-friendly content! Or if it’s an e-mail form, you certainly do not want to receive 900 emails a day with these exact same links and other garbage in them, now do you?
Great, now you understand the importance of captcha’s, but you should also understand how they really work. During my tenure here at Trademark, I’ve installed 3 separate styles of captcha’s on nearly all of our clients numerous websites. We’ll take a look at those:
The first captcha we used here has since been dubbed “The Crayola Capatcha”, noting its large size and squiggly text. Yeah, it’s kind of ugly. It’s also pretty large. But for the most part, it was easy enough for a human to read, and hard enough for a robot to read (oh yes, robots can read!). Number of spam or otherwise unwanted content that got through this captcha? Zero.
Now we have the second edition of the Trademark Captcha. This captcha came about after endless mocking and hatred for the Crayola Captcha by a select…well, only one person :) At any rate, the Crayola Captcha was slowly erased from humankind and in place of it was the, well, we don’t have a name for this one, so lets call it Captcha2. This captcha is slightly smaller, uses a nicer font type, and is overall easier to read for everybody. Noting the ease of use for this captcha, our total number of spam that came through while using this captcha? Zero again. Score.
Now we move on to Captcha3, or what I am hereby dubbing SpamMagnet©. This Captcha came about after more incessant mocking and hatred for Captcha2, because it’s too big and ugly and hard to read, apparently. So here we are. A gorgeous captcha that is easy for users to read, and at long last, it’s small! It’s like going from a big bulky SUV to a nice compact Maserati, complete with 1000w stereo system. Everything was great, everyone was happy, except those 2 poor captchas from the distant past. Who cares, we don’t need them, we have SpamMagnet! We rejoiced in our excellence. For about an hour. Then we got spam on a contact form with this captcha on it. Then another. …and another. Pretty soon, the SpamMagnet lived up to it’s name, and any form we put it on nearly instantly had spam seeping through its megahertz.
Why? Because it was too easy to read. Thats why. OCR software and spambots using such software all over the world had been trying to crack our previous two captchas on several of our higher profile sites. Once they saw this new captcha and how easy it was to crack, the spam came flowing in.
So what do we do now? We go back to Captcha2. Or we invent a new captcha. Moral of the story is, pretty does not necessarily mean most functional. We had a beautiful captcha that cost us bytes and bytes of bandwidth (yes, that’s sarcasm, but spam is annoying no matter what). You need to find a happy medium between your captcha’s ease of use for users, and ease of use for spambots. Unless you enjoy spam. In which case, I’ll send you the code for SpamMagnet!