function statement vs function expression vs function declaration in js code example

Example: function expression vs function declaration

const functionExpression = function(width, height) {
  return width * height;
};

console.log(functionExpression(3, 4));
// Result = 12

function functionDeclaration(width,height){
return width * height;
};

console.log(functionDeclaration(3,4));
//Result = 12