Who doesn’t know them, those mildly irritating requests to type up the letters of a small picture in order to log in somewhere. I knew they are useful as they ensure the site we are logging in to that we are humans instead of spam-bots. So they will know that we really want to buy those tickets, post a comment, etc.
But today I learned there is much more behind Captcha, or reCaptcha as the project is called now that it asks us for 2 words rather than one. In his Ted Talk Luis von Ahn, admitting to being among those that developed Captcha (official site), explains why we now have two words to deal with. It turns out we are all involved in one of the biggest online collaboration ventures of all time while we’re doing this tedious task. From the 2 words shown, one is known to the computer whereas the other is not. It asks us for help in deciphering this word. If we solve the known word correctly, the computer will trust us to get the unknown word right, too. Especially if others provide the same solution to this unknown word.
Digitizing books (via recaptcha site)
So why do we need to help a computer deciphering an unknown word? What use is that to anyone? Well, those unknown words are words from scanned book pages that the computer does not recognise and therefore cannot digitize. If we help it, we help digitize books. The numbers, as mentioned in the TED Talk are staggering.
As a lot of discoveries this discovery that it is possible to combine the usefulness of a Captcha with digitizing books for free led to another idea, explained by Luis von Ahn (blog). He and his team are now working on a language learning programme that will actually help translate the web, for free, in the world’s main languages. While learning for free you contribute to the goal of disclosing the whole of the web to most people in the world.
You can help freely (via recaptcha site)
Next time I am confronted with a Captcha I know what I am contributing to, and will spend those 10 seconds gladly! Not just for digitizing books but also for making possible that other creative ideas will flourish, like the web-translation idea! I might even do it just for the fun of it: Help Digitize Books, too!
