How do you declare variables in JavaScript?

In JavaScript, variables can be declared using the var, let, or const keywords.

Using var (Legacy way):

var variableName = value;
Using let (Recommended for mutable variables):

let variableName = value;
Using const (Recommended for constant variables):

const variableName = value;

Note: The let keyword allows variables to be reassigned, while the const keyword creates variables with read-only values that cannot be changed after declaration. The var keyword is considered legacy and has some scoping quirks, so it is generally better to use let or const instead.

In JavaScript, a variable can be declared using var , let , const keywords. var keyword is used to declare variables since JavaScript was created.