One-time passwords (OTPs) are increasingly used as an enhanced security measure across various industries, offering a dynamic, single-use code for user authentication that expires shortly after issuance, thereby reducing the risk of unauthorized access. OTPs can be delivered through multiple methods, including SMS, email, messaging apps, hardware keys, and authenticator apps, each with distinct benefits and vulnerabilities, such as susceptibility to SIM swapping or phishing attacks. OTPs are primarily categorized into time-based (TOTP) and hash-based (HOTP) types, which differ in how they generate dynamic codes, either through time intervals or counter increments. Despite their effectiveness in preventing replay attacks and providing a user-friendly alternative to static passwords, OTPs have limitations like dependency on delivery reliability and shared secrets, which can be attractive targets for cybercriminals. The adoption of OTPs is widespread in sectors like finance, healthcare, e-commerce, government, and telecommunications, where they are used to secure sensitive transactions and data, with companies like Descope offering tools to integrate OTPs into authentication flows easily.