String Polyfills and Common Interview Methods in JavaScript
Strings are everywhere in JavaScript—from user input to APIs. While JavaScript provides many built-in string methods, understanding how they work internally is what truly sets you apart in intervie...

Source: DEV Community
Strings are everywhere in JavaScript—from user input to APIs. While JavaScript provides many built-in string methods, understanding how they work internally is what truly sets you apart in interviews. In this blog, we’ll explore: What string methods are Why developers write polyfills How to implement common string utilities Popular interview problems 🧠 What Are String Methods? String methods are built-in functions that help manipulate strings. Examples: ```js id="str1" const text = "hello world"; console.log(text.toUpperCase()); // HELLO WORLD console.log(text.includes("world")); // true console.log(text.slice(0, 5)); // hello These methods make string operations easy—but what’s happening behind the scenes? --- ## ❓ Why Developers Write Polyfills A **polyfill** is: > A custom implementation of a built-in method. ### 💡 Why use them? * Understand internal logic * Support older browsers * Practice problem-solving for interviews --- ## ⚙️ Concept: How String Methods Work At a basic le