HTML5 Interview Questions and Answers

Last updated on Feb 08, 2024
  • Share
HTML5 Interview Questions

In the past years, the adoption of HTML5 has increased in an emerging way that more and more companies are using it to deliver rich cross-platform web applications. In this article, we have tried to cover all HTML5 Interview Questions and Answers which are for both basic and advanced levels. Now the question that would come to your mind is- what is HTML5? To develop any web application mainly three components are required i.e. HTML, CSS, and Javascript where HTML is mainly used for designing the website.HTML5 is the latest version which supports all kinds of existing web pages. Every web page you visit today on the internet is written with one or another version of HTML code. HTML5 is one of the highest-paying web technologies so everyone needs to learn basic concepts about this markup language. Companies like Facebook, Amazon, Google, and Youtube have been shifted to HTML5 from Adobe’s Flash for better development. For many years, millions of developers were using this technology but since 2015 it is the most reliable and universal choice to develop web applications. To help you with the same, we have created this article which would clear all your concepts regarding HTML5.

Quick Facts About HTML5
What is HTML5? It is a MARKUP language that is mainly used for creating interfaces rather than analytical works or logical.
What is the latest version of HTML5? HTML5.2 released on December 2017
Who developed HTML5? WHATWG
When was HTML5 first released? 28 October 2014

Most Frequently Asked HTML5 Interview Questions

Here in this article, we will be listing frequently asked HTML5 Interview Questions and Answers with the belief that they will be helpful for you to gain higher marks. Also, to let you know that this article has been written under the guidance of industry professionals and covered all the current competencies.

Q1. What is the difference between HTML and HTML5?
1. The primary language for making web pages. The fifth and latest version of HTML
2. Audio/Video not a part Audio/Video an important part
3. Browser cache used for temporary storage Application cache, web SQL DB, ad web storage used as temporary storage.
Q2. What is an API and list the API's available in HTML5?

API (Application Programming Interfaces) in HTML5 is a way to build different applications using pre-built components. Developers can integrate the relevant features of existing APIs into their new websites.

The APIs in HTML5 are:
  • HTML Web Workers
  • HTML Drag and Drop
  • HTML Application Cache
  • HTML Local Storage
  • HTML Geolocation
Q3. What is semantic elements in html5? List some semantic elements.

A semantic element absolutely describes its that means to each the browser and the developer. Elements such as header, footer and article are all viewed semantically due to the fact they precisely describe the reason for the aspect and the kind of content material that is inner them.

HTML5 Semantic Elements
  • header
  • section
  • nav
  • aside
  • footer etc
Q4. What is the new Structural Elements in HTML5?

HTML5 has introduced the following structural elements for defining different parts of a web page:

  • <header>: Represents HTML's header data
  • <footer>: Footer of the page
  • <nav>: Represents page's navigation elements
  • <article>: Content that is self-contained
  • <section>: Defines sections or groups content into sections
  • <aside>: Refers to side bar contents
Q5. List out the page structure elements of HTML5?
Here is a list of page structure in HTML 5:
  • <header> - Used to define header for a document or a section
  • <nav> - Used to define container for navigation links
  • <section> - Used to define a section inside a document
  • <article> - Used to tag an independent self-contained article
  • <aside> - Defines the content separately (just like a sidebar)
  • <footer> - Used for tagging a footer inside a document or a section
  • <details> - Usd to define any additional details
  • <summary> - Used to define a heading inside the <details> element
Q6. Is HTML5 tags are case sensitive?

No, HTML is not case sensitive. It means that <P> is the same as <p>. However, W3C advises writing HTML in lowercase especially when working on an XHTML document.

Q7. How do you optimize a website's assets & reduce page load time?

Follow these steps to optimize assets and also reduce the page load time of any website:

  • Properly naming all assets.
  • Using a content delivery network (CDN) for media files.
  • Hosting assets on different domains while also reducing DNS lookups
  • Using a cookie-free domain to place assets and splitting them among domains
  • Using CSS Sprites for Images.
  • Disabling etags.
  • Minimizing the use of JS in code.
  • Minimizing inline CSS and using internal and external style sheets.
Q8. What is the use of Scalable Vector Graphics (SVG) in HTML5?

SVGs or Scalable Vector Graphics are used in HTML 5 to display 2-D graphics and its applications in XML which is later on rendered by an SVG viewer. The SVG element is used to contain SVG graphics.


<!DOCTYPE html>

<svg width="100" height="100">
  <circle cx="50" cy="50" r="40" stroke="green" stroke-width="4" fill="yellow" />


Q9. What are the different types of <!DOCTYPE> are available in HTML5?

It is used to create a reference to a Document Type Definition. In HTML 5, Doctype declaration is only needed to enable a standard mode for documents which are written with the HTML syntax. Hence, the Doctype for HTML 5 is short and case-insensitive.

  • <!DOCTYPE html>
  • <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "">
  • <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "">
  • <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "">
  • <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "">
Q10. What is the difference between the SVG and Canvas?
Canvas SVG
1. Resolution dependent Resolution independent
2. No support for event handlers Provides support for event handlers
3. Suitable for graphic-intensive Ideal for creating graphics similar to CAD software
3. Works best for small rendering areas Works even for large rendering areas

Today HTML is considered as the base for all web applications, but with each passing version, many new elements and features have been added to it. So, there is a high chance that the interviewer may ask about the currently used features but as it all starts with HTML so one must learn both. To summarize-

  • Should know the difference between versions of HTML especially HTML4 and HTML5
  • When writing code, always close your HTML tags.
  • Remember HTML is a Markup language, not a programming language.
  • Work with the lists and be more familiar with HTML tables.

Features of HTML5

  • Editing content within element and "required" form attribute
  • Figure tag and SVG element
  • Web fonts
  • Transition and Animation
  • Web Icons
  • Easily implemented audio, video, map with these tags
Reviewed and verified by Umesh Singh
Umesh Singh

My name is Umesh Singh having 11+ experience in Node.JS, React JS, Angular JS, Next JS, PHP, Laravel, WordPress, MySQL, Oracle, JavaScript, HTML and CSS etc. I have worked on around 30+ projects. I lo...