when to use objects in javascript code example

Example 1: objects in javascript

let car = {
  engineNumber: 1234
  brand: 'BMW',
  break: function (){}
}

Example 2: objects javascript

function Dog() {
  this.name = "Bailey"; 
  this.colour = "Golden"; 
  this.breed = "Golden Retriever";
  this.age = 8;
}