CAPTCHA is that annoying technology that asks you to type the characters in an image in a field to post a comment, get an account, or whatever. It’s a spam fighting tool, and one of the more successful ones I might add.
TIME’s got a piece on CAPTCHA which should be pretty interesting reading if you want to know about where it is originating, and what is being done to make sure that it stays successful. Personally, I hate it, but it serves its purpose and probably makes the web a better place, don’t you think?
I implemented one — took me a bit of doing to build my own — thank you for the captcha link, that would have made things easier!
What I don’t understand about it, is why you need captchas to protect forms from bots. You only make your website unfriendly to your customers, human visitors in general.
Same goes when using javascripts to hide decode/encode form elements not only can be bypassed by bots but at the same time you cannot service humans who do not want to have active content enabled with their browsers.
Spam is typically submitted by bots or other automated scripting methods. There’re far superior solutions by using just plain HTML to protect the forms against automated scripts and bots and without visible overhead to the forms.