Back to Basics: A Developer’s Guide to Authentication

Authentication is a crucial aspect of building systems and creating web applications, and could make or break your customer's trust. Microsoft Security (2026) defines authentication as the process that companies use to confirm that only the right people, services, and apps with the right permissions can get organizational resources. It proves who the user is. This differs from authorization which controls what the verified user is allowed to do or what they can access. These two security processes are interconnected, with authentication always happening first followed by authorization. Table of Contents Why should we care? How does the web work? (And why you, as a developer, need to know) How do we authenticate? Multi-factor authentication: Layering your defenses Common Authentication Services: From Factors to Platforms So... which one should you pick? Further Reading & References Why should we care? In the digital age, data is power . Every company and their mother is trying to get ac