JavaScript Syntax

JavaScript syntax is the set of rules that define a correctly structured JavaScript program.

JavaScript Literals

Literals are fixed values, not variables. The two most important types are:

Numbers are written with or without decimals: 10.50, 1001
Strings are text, written within double or single quotes: "John Doe", 'John Doe'

In a programming language, variables are used to store data values. JavaScript uses the var, let and const keywords to declare variables.

javascript

let x;
x = 6;

JavaScript uses arithmetic operators (+ - * /) to compute values:

javascript

(5 + 6) * 10

All JavaScript identifiers are case sensitive. The variables lastName and lastname, are two different variables.

How do you declare a JavaScript variable?

v carName;

variable carName;

var carName;