4 ms·
The reason is that those captchas were helping to OCR-transcribe books. The first word would be known to the system and serve as the actual verification, and th
by gberger 3y ago
The reason is that those captchas were helping to OCR-transcribe books. The first word would be known to the system and serve as the actual verification, and the second word would be unknown and serve as you performing free MTurk work.