JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech III Year WEB PROGRAMMING Previous Question Paper (March - 2021 - R18)

JavaScript is a high-level, interpreted, client-side scripting language primarily used to create interactive and dynamic content on web pages. It allows developers to manipulate the Document Object Model (DOM), handle user events, and perform asynchronous data retrieval.

Control structures in JavaScript dictate the flow of execution:

• Conditional Statements: Used to perform different actions based on different conditions.
if (condition) { // code to execute if true } else { // code to execute if false }
• Switch Statement: Used to select one of many code blocks to be executed.
switch(expression) { case x: // code break; default: // code }
• Loops: Used to execute a block of code repeatedly.
for (let i = 0; i < 5; i++) { console.log(i); }

In JavaScript, objects are the fundamental building blocks for representing real-world entities.

• Object: An object is a standalone entity with properties and type. It is a collection of key-value pairs.
let car = { brand: "Toyota", model: "Corolla" };
• Properties: These are the variables attached to an object that store data or state.
• Methods: These are functions stored as object properties. They define the behavior of the object.
let person = { name: "John", greet: function() { return "Hello"; } };
• Events: Events are actions or occurrences that happen in the system the web page is running in, which the JavaScript code can respond to. Common examples include onclick, onload, and onmouseover.