How does scope chaining help in variable resolution?

Scope chaining is the process JavaScript uses to find variables during code execution.
When you use a variable, JavaScript first looks for it in the current (local) scope.
If it’s not found, it moves outward — checking each outer (parent) scope — until it reaches the global scope.

This sequence of scopes forms the scope chain.

let a = 10;

function outer() {
  let b = 20;

  function inner() {
    let c = 30;
    console.log(a + b + c); // JavaScript finds a → b → c using scope chain
  }

  inner();
}

outer(); // Output: 60

Here’s what happens:

c is found in the inner scope,
b is found in the outer scope,
a is found in the global scope.

In short: Scope chaining helps JavaScript resolve variables correctly by searching from local to global scope, ensuring each variable is accessed from the right place.

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