JavaScript Function Expressions

A JavaScript function expression stores a function inside a variable.

The function is written on the right of an equals sign, and the variable name is used to call it.

Unlike a declaration, a function expression cannot be called before the line that creates it.

Example

const double = function (number) {
  return number * 2;
};

console.log(double(8));

In this example, the function has no name of its own.

It is called through the variable double.