In a blog posting I’ve seen over the blog of Jeremiah Grossman, I saw something horrible. Today, we know what CAPTCHAs are and that it’s a simple method to protect for example a guestbook from spam entries. Now, this blog posting shows the following CAPTCHA:

OK, that’s really horrible I think and this because of the following points:

• Because the only characters which are visible most of the time, are the characters of the code and so an analysing tool can detect the code very easy
• The characters which are not part of the CAPTCHA code become visible always at the same time in the loop and so it’s not that hard to detect them and filter out the real code
• It’s really hard to read, even for humans

Because of this reasons I think nobody should use this kind of CAPTCHAs because they aren’t secure at all and because people might think that they are useing them and wondering afterwards, why an automated bot was able to trick their CAPTCHA.