CAPTCHA which is the short version of completely automated public Turing test to tell computers and humans apart,. CAPTCHAs are designed to stop spam bots.
According to wikipedia a spambot is an automated computer program designed to assist in the sending of spam. Spambots create fake email accounts and accounts on blogs and forums to send spam.
CAPTCHAs are designed so that only a real person can read them and not another computer. The words displayed are actually an image rather than text. A real person needs to read the text and enter the words in the CAPTCHA to prove they are a real person.
The problem with CAPTCHAs are they are not accessible to people who are blind or have a vision impairment. Some versions of CAPTCHAs use audio but it often not very accessible either. People who are dyslexic, colour-blind, new to computer and older users can also find CAPTCHA difficult to use.
There are some web designers and people with disabilities who argue CAPTCHA contravenes the Disability Discrimination Act. Whilst I’m not a legal expert or web design expert I would agree as anything that consistently makes it difficult for any user to use the website has to be discriminatory.
I have supported the recently launched campaign to ask very popular websites such as Google, Facebook and Twitter to use other technologies instead of CAPTCHA to stop spam bots. This would allow more people to easily use the Internet.
I hope you will consider adding your support to the campaign so the Internet will become easier for everyone to use.