Scopes in JavaScript
In the last blog, we looked at Hoisting — how JavaScript moves declarations before execution.
Now, let’s talk about another core concept: Scope.
What is scope?
Scope is all about where you variables and function are accessible in your code
Types of Scope in JavaScript
1. Global Scope
A variable declared outside any function or block lives in the global scope.it can be accessed from anywhere in you code
2. Function Scope
Variables declared inside a function are only accessible within that function.
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3. Block Scope
let and const have block scope — meaning they exist only inside the { } where they are defined.
var does not have block scope — it ignores { } and acts as if declared in the function/global scope.4. Lexical Scope (Closures)
Functions can access variables from the scope they were created in — even if you call them somewhere else.
Why Scope Matters
- Prevents naming conflicts.
- Keeps your code organized.
- Helps manage memory by controlling variable lifetime.
In the next blog, we’ll dive into a new concept — and trust me, it’s going to be an interesting one!
