[berkman] Luis von Ahn on free lunches, captcha, and tags

Luis von Ahn of Carnegie Mellon University is giving a Berkman lunchtime talk. [NOTE: I’m liveblogging. I’m making mistakes, leaving stuff out, paraphrasing, getting things wrong. This is an unreliable record.] Luis invented captchas, the random characters you have to type in to convince a web page that you are a human and not a […]