CAPTCHAs are those now ubiquitous challenges you encounter to prove that you’re a human and not a bot when you go to log in to many websites.
Websites and mobile apps have long been attacked by bots on a massive scale[1]. Those malicious bots[2] are programmed to automatically consume a large amount of computing resources, post spam...
Read more https://theconversation.com/captchas-the-struggle-to-tell-real-humans-from-fake-232369