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<ahref=https://en.wikipedia.org/wiki/Proof_of_work>proof-of-work</a> based
at the click of a button) and gets out of the way.</p><h2id=how-does-it-work>How does it work?</h2><p>mCaptcha uses SHA256 based proof-of-work(PoW) to rate limit users.</p><p>When a user wants to do something on an mCaptcha-protected website,</p><ol><li><p>they will have to generate proof-of-work(a bunch of math that will
takes time to compute) and submit it to mCaptcha.</p></li><li><p>We’ll validate the proof:</p></li></ol><ul><li>if validation is unsuccessful, they will be prevented from accessing
the destination website</li><li>if validation is successful, read on,</li></ul><olstart=3><li><p>They will be issued a token that should be submit along with the
request/form to the destination website.</p></li><li><p>The destination website validates the submitted token with
mCaptcha before processing the request.</p></li></ol><p>The whole process is automated from the user’s point of view. All they
have to do is click on a button to initiate the process.</p><h2id=okay-but-what-about-bad-actors>Okay, but what about bad actors?</h2><p>mCaptcha makes interacting with websites (computationally)expensive for
to their request.</p><h2id=why-use-mcaptcha>Why use mCaptcha?</h2><ul><li><strong>Free software, privacy focused</strong></li><li><strong>Seamless</strong> UX — No more annoying CAPTCHAs!</li><li><strong>IP address independent:</strong> your users are behind a NAT? We got you covered!</li><li><strong>Automatic bot throttling</strong></li><li><strong>Resistant to replay attacks:</strong> proof-of-work configurations have short lifetimes(30s) and can be used only once. If a user submits a PoW to an already used configuration or an expired one, their proof will be rejected.</li></ul><h2id=how-to-migrate>How to migrate?</h2><p>Our client libraries are mostly compatible with reCAPTCHA and hCaptcha.
A detailed guide will be published soon.</p><h2id=our-philosophy>Our Philosophy</h2><p>Man has has come so far only because our ancestors chose to
