# Closures Continued: Lexical vs. Dynamic Scope

It is helpful to contrast lexical scope with **dynamic scope** to understand why closures work the way they do.

## Lexical Scope (JavaScript)

Scope is determined by where the function is *defined* in the source code. The inner function "remembers" the environment where it was created.

## Dynamic Scope

Scope is determined by where the function is *called* (the call stack).

## Example Comparison

```javascript
const value = "Global";

function printValue() {
  console.log(value);
}

function wrapper() {
  const value = "Local";
  printValue();
}

wrapper();
```

*   **In JavaScript (Lexical):** `printValue` was defined in the global scope, so it sees `value = "Global"`. The output is "Global".
*   **If JavaScript were Dynamic:** `printValue` is called inside `wrapper`, so it would see `wrapper`'s `value`. The output would be "Local".

Closures rely on lexical scoping to persist data. If scope were dynamic, the data a function accesses would change depending on who called it, breaking the encapsulation that closures provide.

[[programming/javascript/vanilla/closures]]
[[programming/javascript/vanilla/javascript]]