Web Programming Web Performance and Optimization

Question 1

What does minification do to JavaScript or CSS files?

Accepted Answer

Removes whitespace, comments, and shortens names to reduce file size

Answer

Encrypts the file content

Answer

Compresses files using gzip

Answer

Combines multiple files into one

Question 2

What is the purpose of browser caching in web performance?

Accepted Answer

To save copies of resources locally so they don't need to be re-downloaded on repeat visits

Answer

To store user passwords securely

Answer

To cache database queries on the server

Answer

To store form data temporarily

Question 3

What is lazy loading in web development?

Accepted Answer

Deferring the loading of non-critical resources until they are needed

Answer

Loading all resources at page startup

Answer

Caching resources for offline use

Answer

Preloading resources before they are requested

Question 4

What does CDN stand for and what is its primary purpose?

Accepted Answer

Content Delivery Network — distributes content across servers geographically closer to users

Answer

Centralized Data Network — stores all website data in one place

Answer

Client Data Node — caches data on the client side

Answer

Core DNS Network — manages domain name resolution

Question 5

What is the purpose of GZIP compression in web performance?

Accepted Answer

To compress text-based resources like HTML, CSS, and JS before sending them over the network

Answer

To encrypt web traffic

Answer

To compress images into smaller files

Answer

To minify JavaScript code

Question 6

What is the Largest Contentful Paint (LCP) metric used for?

Accepted Answer

Measuring the load time of the largest visible content element, a Core Web Vital

Answer

Measuring total page weight in kilobytes

Answer

Counting the number of DOM elements on a page

Answer

Measuring server response time