Background: Why Did OTP Appear? Traditional login relies on “passwords”—something only you know. But as we discussed in the previous article, passwords are vulnerable to leaks, guesses, and theft....

In the previous article, we learned how TOTP generates one-time passwords using a secret key. But here’s a question: where does this secret key come from, and how is it stored safely? This is wher...

When we talk about account security, “using a strong password” is the most common advice. But in reality, passwords alone are far from enough. That’s where Two-Factor Authentication (2FA) comes in....

When you validate user input, you’ll see values like "42", " 3.14 ", or "1e3". typeof x === 'number' misses numeric strings, while isNaN(x) can be tricked by coercion. The is-number utility return...

Last weekend, I pushed the latest markdown article to Stan Blog1. Everything looked fine in the rich-text editor, but once it landed on the portal, every unordered list sat there—completely naked—n...