A CAPTCHA is “a type of challenge-response test used in computing to determine whether or not the user is human” (source). More specifically this little rant is aimed at the variety of images containing letters and/or numbers which may be distorted, placed on a background or otherwise messed with to supposedly prevent non-humans from getting past a certain point. I hate them.
You may think it odd that someone who has two public scripts both with CAPTCHA capability should hate them, but it is true. I only implemented the bloody things into my scripts because it was what ‘the people’ wanted.
Generally, I can see the point of CAPTCHAs. They do help to reduce spam at some sites, but at what cost? If I, a fully able human being with perfect eyesight and a decent browser, have problems seeing captchas or getting the letter combinations right, what hope do those with poor eyesight or other reading/visual disabilities? Must they be relegated to a silent corner, never allowed to join a website or post a comment again, for fear of angering the giant CAPTCHA making machine monster thingy?
I wish that people would think before inserting CAPTCHAs on parts of their website that simply do not need it (for there are other tools which can help prevent spam which do not require visual confirmation). I also wish that people would clearly mark where CAPTCHAs are being used so as not to catch people out — if you’re going to put a captcha on your weblog, put it on the page with the rest of the comment form. By placing it on a confirmation page, it is very likely that I’m going to have browsed away in a separate tab and closed the page assuming that my comment has gone through without even looking.
Simply put: before adding a CAPTCHA, make sure you have exhausted all other options. For my sake (think of my blood pressure), for the sake of your poor-sighted victims and those with reading difficulties. Remember, if spammers can get past Hotmail and Yahoo’s complex CAPTCHAs, there’s no way in Hell that your freebie WordPress plugin is going to stop them in the long run. You’ll be the one losing out in the end.