CAPTCHAs

CAPTCHAs are those little checks that you see on web pages where you are asked to recognise the word shown in a graphic image and type it in.

 

Mindhacks has a fascinating blog entry about them – including how spammers are using human weakness for sex into breaking the protection of CAPTCHAs.

 

Equally fascinating is the update to the entry pointing to a Google video of Luis von Ahn talking about them. But I note the irony that the human responsible for captioning the talk made a transcription error over von Ahn’s name…