The basic idea is, a random, known image is created and you have to type in what the computer created. If it matches, then a person typed it. I have heard that you can be "close" (off by one letter) and still be accepted, but I haven't tested this myself.
The second word is the fun (read: nerd-friendly) part. It's not a known word. It's part of a project to scan in old books. When the computer has a problem with a word or letter combination, it's put into the Captcha system as the second word. It then tallies what humans think it is, and figures out the letter(s) by consensus.
We're all unpaid labour. I'm not sure how I feel about this yet. Am I part of a great endeavour, or am I being forced to supply my time and effort for free?
do you have a source for the factoid about the captcha system?
ReplyDeleteGoogle
ReplyDeletecaptcha two words
and ye shall find.