JavaScript Reference

Quick Reference

JavaScript arithmetic operators are used to perform arithmetic between variables and/or values.

Addition

let x = 3 + 2; // answer: 5
let x = 4;
let y = x + 2; // answer: 6

Subtraction

let x = 3 - 2; // answer: 1
let x = 4;
let y = x - 2; // answer: 2

Multiplication

let x = 3 * 2; // answer: 6
let x = 4;
let y = x * 2; // answer: 8

Division

let x = 3 / 2; // answer: 1.5
let x = 4;
let y = x / 2; // answer: 2

Exponentiation

Using ** between two numbers is the same as using an exponent.

For example, 3 ** 2 is the same as 32.

let x = 3 ** 2; // answer: 9
let x = 4;
let y = x ** 2; // answer: 16

Modulus

Using % between two numbers divides the first number by the second number and returns the remainder.

let x = 3 % 2; // answer: 1
let x = 4;
let y = x % 2; // answer: 0 (there is no remainder)

JavaScript Notes:

  • When using JavaScript, single or double quotation marks are acceptable and work identically to one another; choose whichever you prefer, and stay consistent
  • JavaScript is a case-sensitive language; firstName is NOT the same as firstname
  • Arrays count starting from zero NOT one; so item 1 is position [0], item 2 is position [1], and item 3 is position [2] … and so on
  • JavaScript variables must begin with a letter, $, or _
  • JavaScript variables are case sensitive (x is not the same as X)

We’d like to acknowledge that we learned a great deal of our coding from W3Schools and TutorialsPoint, borrowing heavily from their teaching process and excellent code examples. We highly recommend both sites to deepen your experience, and further your coding journey. We’re just hitting the basics here at 1SMARTchicken.