Web Programming Web Performance and Optimization 2

Question 1

What is code splitting in the context of web applications?

Accepted Answer

Breaking a JavaScript bundle into smaller chunks loaded on demand

Answer

Code splitting breaks a large JavaScript bundle into smaller chunks that can be loaded on demand or in parallel, reducing the initial bundle size and improving load time.

Question 2

What does the HTTP/2 protocol improve over HTTP/1.1?

Accepted Answer

Multiplexing — allowing multiple requests over a single connection simultaneously

Answer

HTTP/2 introduces multiplexing, which allows multiple HTTP requests and responses to be sent simultaneously over a single TCP connection, eliminating HTTP/1.1's head-of-line blocking.

Question 3

What is the purpose of image optimization in web performance?

Accepted Answer

To reduce image file sizes while maintaining acceptable visual quality, improving load times

Answer

Image optimization reduces file sizes through compression, proper formatting (WebP, AVIF), and appropriate dimensions, significantly improving page load performance since images are often the largest page assets.

Question 4

What is a service worker in web development?

Accepted Answer

A script that runs in the browser background, enabling offline functionality and push notifications

Answer

A service worker is a JavaScript file that runs in the background separate from the web page, acting as a network proxy to enable offline capabilities, caching, and push notifications.

Question 5

What does the 'render-blocking' term mean in web performance?

Accepted Answer

Resources like CSS or JavaScript that must load before the browser can render the page

Answer

Render-blocking resources are files (usually CSS or synchronous JS in the <head>) that the browser must download and process before it can render any of the page content.

Web Programming Practice Test

Web Programming Practice Test

Web Programming Web Performance and Optimization 2