Mark Styles has posted over at Weblog Tools a post on CAPTCHAs (wikipedia’s page on them here) which makes some good points about why they might not be the best solution for stopping comment spam on a blog. Here’s a few of his main points:
- Any extra work required to comment is likely to deter some people from commenting at all.
- Sometimes the images are so distorted they’re almost impossible to read, even with perfect eyesight.
- CAPTCHAs are hackable. Spammers are smart, they can get past many of our barriers.
- Visually impaired users are completely excluded (although there are audio CAPTCHAs available now).
- Dyslexics have a hard time too.
- There are better and less intrusive solutions.