CAPTCHA: History, Development, and Its Role in Cybersecurity and Anti‑Fraud Strategies
This article reviews the origin and evolution of CAPTCHAs, examines early applications and OCR attacks, describes the three generations of reCAPTCHA and emerging verification methods, and discusses how CAPTCHAs are used to raise attack barriers, filter malicious traffic, and support risk assessment in modern anti‑fraud systems.
