How to make variables on JavaScript

Find out how to use variables in JavaScript, with examples of the declaration and initialization of variables.

Creating Variables in JavaScript

A variable is a named memory location used to store data values. In JavaScript, a variable can be declared and assigned a value in one statement.

var myVar = 5;

The variable myVar is assigned the value 5. Variables can also be declared without an initial value.

var myVar;

The variable myVar is declared and initialized with the default value of undefined.

Variables can also be declared with a comma-separated list of variable names.

var myVar1, myVar2, myVar3;

In this example, three variables are declared and initialized with the default value of undefined.

Variables can also be declared and assigned values in a comma-separated list.

var myVar1 = 5, myVar2 = 10, myVar3 = 15;

In this example, three variables are declared and assigned values. The variable myVar1 is assigned the value 5, myVar2 is assigned the value 10, and myVar3 is assigned the value 15.

Variables can also be declared and assigned values using a shorthand syntax.

var myVar1 = 5,
    myVar2 = 10,
    myVar3 = 15;

In this example, the variables are declared and assigned values using the same syntax as the previous example. The only difference is that the variables are declared and assigned values on separate lines.

Variables can also be declared and assigned values using object literal syntax.

var myVars = {
    myVar1: 5,
    myVar2: 10,
    myVar3: 15
};

In this example, an object literal is used to declare the variables and assign their values. The object literal syntax is a convenient way to declare multiple variables at once.

Variables can also be declared using the let keyword. The let keyword declares a variable whose scope is limited to the block, statement, or expression on which it is used.

let myVar = 5;

In this example, the variable myVar is declared using the let keyword and is assigned the value 5.

Variables can also be declared using the const keyword. The const keyword declares a variable whose value cannot be changed.

const myVar = 5;

In this example, the variable myVar is declared using the const keyword and is assigned the value 5. The value of this variable cannot be changed.

In JavaScript, variables can be declared using the var, let, and const keywords. Variables can be declared and assigned values in a single statement or in a comma-separated list. Variables can also be declared and assigned values using object literal syntax.