HTML5 Application Development Fundamentals Flashcards

What is the purpose of CSS media queries in responsive web design?

Answer: Applying different styles based on device characteristics like screen width

CSS media queries apply different style rules based on device characteristics such as screen width, height, or orientation, enabling responsive designs that adapt to different devices.

Which JavaScript method is used to make asynchronous HTTP requests to a server?

Answer: fetch()

The fetch() API provides a modern, promise-based way to make asynchronous HTTP requests to servers and APIs, replacing the older XMLHttpRequest (XHR) approach.

What does the 'alt' attribute on an HTML element provide?

Answer: Alternative text displayed when the image cannot load and read by screen readers

The alt attribute provides a text alternative for images that is displayed when the image fails to load and is read by screen readers for accessibility.

What is the purpose of the HTML5 elements like , , , and ?

Answer: Providing meaningful structure that improves accessibility and SEO

HTML5 semantic elements convey meaning about the content they contain, helping browsers, screen readers, and search engines understand the document structure.

What is the difference between sessionStorage and localStorage in HTML5?

Answer: sessionStorage is cleared when the browser tab is closed; localStorage persists indefinitely

sessionStorage stores data only for the duration of a browser session (cleared when the tab closes), while localStorage persists data with no expiration until explicitly cleared.

Which HTML5 API allows web applications to work offline by caching resources?

Answer: Service Worker API

Service Workers are JavaScript files that run in the background, intercepting network requests and caching resources to enable offline functionality and faster load times.