understanding javascript objects code example

Example 1: creating an object javascript

let obj = {
// fields
  name:"value",
  num: 123,
//methods
  foo: function(){}
  
}

Example 2: objects in javascript

let object = {
  'key1': 'value1',
  'key2': 'value2',
  'keyn': 'valuen',
};
console.log(object);

Example 3: objects in javascript

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