Multi-factor authentication (MFA) is a security system that requires users to provide multiple forms of verification to access services, enhancing protection against digital threats by creating layered defenses. MFA, which has become increasingly popular, can prevent over 99.9% of account compromise attacks and significantly reduce phishing attempts. It involves using two or more factors, such as knowledge (passwords), possession (devices or tokens), and inherence (biometrics). MFA not only improves security by mitigating risks associated with stolen passwords but also balances user experience by allowing flexible authentication methods that suit user preferences and security needs. It is crucial for regulatory compliance in industries like finance and healthcare, aligning with standards such as GDPR and PCI DSS. Various types of MFA factors exist, including context-based factors like location and time, which enhance security by assessing the risk of login attempts. Subsets of MFA, such as step-up and adaptive authentication, offer dynamic security measures based on user behavior and risk levels. Implementing MFA can be complex, but platforms like Descope simplify the process by providing tools to integrate MFA efficiently into existing systems.