var let const javascript

• var:

  • The traditional way of declaring variables.
  • Functional scoped
  • Can be redeclared

• let:

  • Introduced in ES6 (2015), let allows you to declare block-scoped variables.
  • Block scoped
  • Cannot be redeclared

• const:

  • Also introduced in ES6, const declares variables that cannot be reassigned after their initial assignment.
  • Block scoped
  • Cannot be redeclared & has to be initialized while declaring

var x; // Declaration only
let y = 10; // Declaration and initialization
const z = "Hello"; // Declaration and initialization (must be initialized)

• Variable Scope JavaScript
• Variable Shadowing Javascript
• Illegal Shadowing Javascript
• Declaration initialization Javascript
• Execution Context Javascript
• Temporal Dead Zone Javascript
• Hoisting Javascript

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