window.pageXOffset is an alias of window.scrollX.
window.pageYOffset is an alias of window.scrollY.

click – when the mouse clicks on an element (touchscreen devices generate it on a tap).
contextmenu – when the mouse right-clicks on an element.
mouseover / mouseout – when the mouse cursor comes over / leaves an element.
mousedown / mouseup – when the mouse button is pressed / released over an element.
mousemove – when the mouse is moved.

keydown va keyup - klaviatura tugmasi bosilganda va qo'yib yuborilganda.

<input type="button" id="button" value="Button">
<script>
  button.onclick = function() {
    alert('Click!');
  };
</script>

<input id="elem" type="button" value="Click me"/>
<script>
  function handler1() {
    alert('Thanks!');
  };
  function handler2() {
    alert('Thanks again!');
  }
  elem.onclick = () => alert("Hello");
  elem.addEventListener("click", handler1); // Thanks!
  elem.addEventListener("click", handler2); // Thanks again!
</script>

button.addEventListener("click", () => alert("1"));

button.removeEventListener("click", () => alert("1"));

const fruits = ["Banana", "Orange", "Apple", "Mango"];
console.log(fruits);

const person = {
name: "Alice",
age: 15,
city:"New York"
};
console.log(person);

const person = {firstName:"John", lastName:"Doe", age:50, eyeColor:"blue"};

const person = {
  firstName: "John",
  lastName: "Doe",
  age: 50,
  eyeColor: "blue"
};

const person = {};

// Add Properties
person.firstName = "John";
person.lastName = "Doe";
person.age = 50;
person.eyeColor = "blue";

objectName.propertyName
objectName["propertyName"]

const person = {
    firstName: "John",
    lastName: "Doe",
    age: 50,
    eyeColor: "blue"
  };
  
  delete person.age;
  console.log(person);

const person = {
  firstName: "John",
  lastName: "Doe",
  id: 5566,
  fullName: function() {
    return this.firstName + " " + this.lastName;
  }
};

// `fullName` metodini chaqirish va uning natijasini konsolga chiqarish
console.log(person.fullName());