Scope is the set of variables that’s visible to a part of the program.
In JavaScript we have a 3 different scopes:
- global scope
- function scope
- block scope
In JavaScript, everything that’s not defined inside a function or block is attached to the global object.
Take this example:
var age = 20
We define an age variable.
We can always reference this variable inside any other function or loop or anywhere, using age.
const age = 20
console.log(age) //20
let age = 20
console.log(age) //20
Lessons this unit:
| 0: | Introduction |
| 1: | ▶︎ Global scope |
| 2: | Function scope |
| 3: | Block scope |
| 4: | Shadowing |
| 5: | Hoisting |
| 6: | Closures |
| 7: | An issue with `var` variables and loops |
| 8: | The event loop |