What types are there in JavaScript?

JavaScript has the following main data types:

• Primitive types:

  • Number — numbers (integers and floating-point)
  • String — strings
  • Boolean — logical values (true or false)
  • Undefined — the value of a variable that has not been assigned a value
  • Null — a special value meaning "no value"
  • Symbol — unique and immutable identifiers
  • BigInt — for representing integers of arbitrary length

• Objects:

  • Object — a collection of key-value pairs
  • Arrays, functions, dates, and other structures are objects with additional functionality

Example of defining variables of different types:

let num = 42; // Number
let str = "Hello"; // String
let flag = true; // Boolean
let undef; // Undefined
let empty = null; // Null
let sym = Symbol('id'); // Symbol
let bigIntNum = 9007199254740991n; // BigInt
let obj = { name: "Ivan" }; // Object