Cloudflare announced plans to drop Google’s reCAPTCHA service in favor of hCaptcha last week on the official company blog.
Cloudflare offers many features for webmasters and site owners. One of the features acts like a firewall. It blocks known malicious traffic automatically, allows traffic by humans, and displays a captcha if traffic is encountered that could be malicious or legitimate.
Captcha, which stands for Completely Automated Public Turing Test to Tell Computers and Humans Apart, are displayed in the latter cases as a verification step. Ideally, captchas are designed so that humans can pass them easily while bots will fail to pass them.