microsoft-authentication-library-for-js

MSAL for JS is a security-focused library that enables JavaScript applications to authenticate users and obtain tokens for accessing Microsoft cloud services and APIs. It is designed for developers building web apps, single-page applications, or Node.js backends who need to integrate with Microsoft Entra ID (formerly Azure AD) for identity management. The library is interesting because it simplifies complex OAuth 2.0 and OpenID Connect flows, supports multiple authentication scenarios (including B2C and national clouds), and helps enforce secure token handling to protect user data.