Types of Scope

1. Global Scope

• Variables declared outside any function or block
• Accessible throughout the entire program
• Created using var, let, or const at the top level

const globalVar = "I'm global";

function testScope() {
  console.log(globalVar); // Accessible
}

2. Function/Local Scope

• Variables declared inside a function
• Only accessible within that function
• Each function creates its own scope

function myFunction() {
  var localVar = "I'm local";
  console.log(localVar); // Accessible
}
// console.log(localVar); // ❌ Error: localVar is not defined

3. Block Scope

• Variables declared inside a block {}
• Only accessible within that block
• Created using let and const (not var)

if (true) {
  let blockVar = "I'm block-scoped";
  const alsoBlock = "Me too";
  // Both accessible here
}
// console.log(blockVar); // ❌ Error: blockVar is not defined

4. Lexical/Static Scope

• Inner functions can access variables from outer scope
• Scope is determined by the location where variables are declared

function outer() {
  const message = "Hello";
  function inner() {
    console.log(message); // Can access message
  }
  inner();
}