let x = 5;

x = 5;

const x : 5;

var x = 5;

string, number, boolean, null, undefined, symbol, object

array, function, set

date, time, list

integer, float, character

Apply Math.round(string)

Convert using toString(string)

Use stringToNumber(string) method

Use Number(string), parseInt(string), or parseFloat(string) to convert a string to a number.

To store data in variables

The purpose of a function in JavaScript is to encapsulate code for reuse and to perform specific tasks.

To define global variables

To create HTML elements

Function expression can be called before its definition.

Function declaration can only be used in strict mode.

Function declaration is hoisted and can be called before its definition, while function expression is not hoisted and must be defined before it can be called.

Function declaration and function expression are the same.

Scope is the method of error handling in JavaScript.

Scope is a type of JavaScript function.

Scope refers to the speed of JavaScript execution.

Scope in JavaScript defines the visibility and lifetime of variables and functions.

You must declare the outer variable as global to access it in the inner function.

You can reference the outer variable directly by its name in the inner function.

You can only access the outer variable by passing it as an argument.

Inner functions cannot access outer variables at all.

Data Object Model

Document Object Module

Dynamic Object Model

Document Object Model

document.getElementById('yourElementId');

getElementById('yourElementId');

document.selectById('yourElementId');

document.getElement('yourElementId');

Use the 'textContent' property in JavaScript.

Use the 'innerHTML' property in JavaScript.

Change the CSS style of the element.

Use the 'setAttribute' method to modify the element.

Call the appendChild method on the document to add an element.

Use document.getElementById('elementId') to create a new element.

Modify the innerHTML property of an existing element to add a new element.

Use document.createElement('elementType') and append it to the DOM.

Event handling is a method for creating animations in JavaScript.

Event handling refers to the process of defining variables in JavaScript.

Event handling is the way to manage memory allocation in JavaScript.

Event handling in JavaScript is the mechanism that allows developers to execute code in response to user actions or events.

Use element.remove() or parentNode.removeChild(element).

Call removeElement(element) method.

Use element.delete() to remove an element.

Set element.style.display to 'none' to hide it.

The 'this' keyword is used to create new objects.

The 'this' keyword is used to refer to the current execution context or object.

The 'this' keyword is used to declare global variables.

The 'this' keyword is a way to define functions in JavaScript.