What is a function in JavaScript?

Short answer: A function is a block of reusable code that performs a task or returns a value. Example: function greet(name) { return `Hello, ${name}!`; } console.log(greet("Sandeep"));

Example code

A function is a block of reusable code that performs a task or returns a value. Example: function greet(name) { return `Hello, ${name}!`;
} console.log(greet("Sandeep"));

Real-world example (ShopNest)

ShopNest’s browser cart uses modern JavaScript: fetch APIs with async/await, modules, and clear error handling.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.