10 HTML5 Developer interview questions and answers

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What key features distinguish HTML5 from previous versions?

HTML5 is often used as a buzzword for modern web technologies—so it should come as no surprise that most front-end web developers will have it in their repertoire. Use this question to see if your prospective developer will take full advantage of the features that make HTML5 a core component of the modern web. Answers might include:

  • The ability to run script as a background process without compromising page performance via web workers.
  • New ways to divide up your content with semantic elements like the <header>, <footer>, <article>, and <section> tags.
  • The ability to embed graphics, audio, and video content with the <canvas>, <audio>, and <video> tags.
  • JavaScript API extensions like geolocation, drag-and-drop, local storage, and the Application Cache.
  • Forms 2.0 controls like <time>, <date>, <calendar>, <email>, <url>, and <search>.

Which browsers support HTML5? Is HTML5 backwards compatible with older browsers?

The latest versions of Google Chrome, Mozilla Firefox, Opera, Apple Safari, Internet Explorer, and Microsoft’s Edge all support HTML5 to varying extents. HTML5 is backwards compatible by design, allowing developers to create fallback content for older browsers. The more nuanced answer will also point out that not all browsers interpret HTML5 the same way, and not all the new features found within HTML5 have been adopted by all browsers. A developer must still check compatibility for each browser when choosing to use newer features.

What is the correct way to use the following HTML5 semantic elements: <header>, <footer>, <article>, and <section>?

HTML5’s new semantic elements exist to help HTML better reflect the type of content that actually appears on webpages. While you could stuff everything into <div> tags, it can be more useful for larger applications to define clear sections that can be mapped for displaying different types of content.

  • The <header> element is used for navigation and introductory information about a page—things like the author’s name, date of publication, or the table of contents are often stored here.
  • The <footer> element is often regarded as the best place to store copyright information, privacy policies, and website terms. It can also serve as a good place to incorporate things like the sitemap or additional links for SEO purposes.
  • The <article> element generally houses content—individual blog posts, news articles, and other stand-alone pieces are contained here.
  • The <section> element exists for design flexibility—it can be used to divide up content thematically into different sections of a webpage.

What is Web Forms 2.0? Briefly describe some of the new features.

Web Forms 2.0 extends the form features of HTML4 to include a greater degree of semantic markup. Some of these key new features are described below.

  • New type attributes were added to the <input> element, including “datetime,” “month,” “week,” “time,” and “url” among other useful inputs. Coders can now achieve greater control over the types of information that can be input into a web form without the hassle of writing additional code.
  • The <output> element was added to simplify representing the result of a calculation or script.
  • HTML5 added a new “placeholder” attribute that can be used in <input> and <textarea> elements to hint to the user what can be entered into the field.
  • The “required” attribute was introduced to alleviate the need for client-side validation to handle cases where a user has neglected to fill in a mandatory entry field within a web form.

How would you create a 500x500-pixel with an orange 300x100-pixel rectangle within the top right corner of the square, 20 pixels from the top and left edges of the canvas?

One possible solution is depicted below.

<canvas id="c" width="500" height="500"></canvas>

  var canvas = document.getElementById( "c" );
  var drawing_context = canvas.getContext( "2d" );
  drawing_context.fillStyle = "orange";
  drawing_context.fillRect( 20, 20, 300, 100 );

What is HTML5 Web Storage?

HTML5 Web Storage is a convenient alternative to cookies, which allows a webpage to store data locally within the user’s browser as name/value pairs. Web Storage is faster and more secure than cookies. It is also able to store more data, capping off at approximately 5MB. Data is only accessed as needed and information is never transferred to the server. While Web Storage is more secure than cookies, it is not encrypted and sensitive items like security tokens should never be stored there.

Can you explain the difference between localStorage and sessionStorage?

Data stored on a user’s browser via localStorage will remain on the user’s computer until they clean their browser or a web app deletes it. Data stored using sessionStorage is temporary, and will only remain until the top-level window or tab running the script is closed. It is worth noting that the scope of sessionStorage is confined to the window that it is operating within—opening multiple tabs displaying content from the same origin will create separate sessionStorage data that cannot be altered by scripts running in other tabs.

How would you use HTML5 to embed a video stored at “http://www.example.com/amazing_video.mp4” with user controls? Make it any size you like.

This question is a simple open-ended HTML test to give coders room for embellishments. While there are many ways to do this, one potential solution is depicted below.

<video width="500" height="400" controls>
  <source src="http://www.example.com/amazing_video.mp4">

Alternatively, here is a more straightforward approach.

<video src="http://www.example.com/amazing_video.mp4" width="500" height="400" controls></video>

What is the Geolocation API and why would you use it?

The HTML5 Geolocation API allows users to share their location with a website. This is a useful feature that asks a user permission to share their latitude and longitude with the app to receive the benefits of location-aware features, such as the ability to present the landing page of the business closest to the user’s location.

What is the purpose of web sockets' “Socket.readyState” attribute?

This attribute is used to assess the state of a connection using the following four values:

  • The value “0” indicates that the connection has not been established.
  • The value “1” indicates that the connection is established and communication is possible.
  • The value “2” indicates the closing handshake.
  • The value “3” indicates a closed or blocked socket.
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  • $35 hourly
    Eyamin H.
    HTML5 Developer
    • 5.0
    • (189 jobs)
    Magura, DHAKA
    vsuc_fltilesrefresh_TrophyIcon HTML5
    MySQL Programming
    WordPress Plugin
    CMS Development
    Theme Development
    PSD to HTML
    CSS 3
    Hi. Thank you so much for coming here. I'm WordPress developer. I have been working with WordPress last 6 years. I have developed a wide range web development project. Experience ================= *** html5 , css , css3 , sass , bootstrap , Custom Responsive , JavaScript , jQuery , jQuery Ui , Ajax , Gulp Automation , php , WordPress , WordPress Theme And Plugin Development , Git , Bit-bucket , GitHub ****** #Squarespace Website Builder is my new crush. :) Provide Services =============== ** Full Functionality WordPress theme development with Woo-commerce Support. ** Custom WordPress Plugin Development ** Psd to WordPress. ** Pixel Perfect WordPress Website using page Builder. * Elementor Builder * Divi Builder * Visual Composer * SiteOrigin * Beaver Builder * Fushion Builder ** WordPress Theme Customization any kind of theme. ** Woo-commerce for eCommerce website . * Have Very good knowledge about product feature and attribute ** Psd to html. ** Psd to html with Bootstrap. ** Any Kind of WordPress problem. ** 100% responsive Website. ** Any kind of JQuery, JavaScript Problem. ** Site page Speed. (gtmetrix) , )( Google PageSpeed Insights). My aim is to give you back your project within your right time. and to work in a standard way where clients will be "SATISFIED" of my work .
  • $35 hourly
    Kimera M.
    HTML5 Developer
    • 5.0
    • (4 jobs)
    Kampala Central Division, C
    vsuc_fltilesrefresh_TrophyIcon HTML5
    Tailwind CSS
    React Bootstrap
    RESTful API
    Material Design
    CSS 3
    Adobe XD
    Hi Thanks for stopping by👋 Online presence of any business is a major attribute to it's success. Every business should always make it's brand known to the general public which can easily translate into revenue. Do your needs fit into any of these questions listed below? Send me a message and we discuss about your project. 🤔Do you have an XD/Figma designs that you want to translate into reusable code using HTML, CSS, JavaScript or React Js? 🤔 Do you want a website for any business but you don't know where to start from? 🤔 Is your website not responsive enough to be used on all platforms and you want it made responsive? 🤔 Want to add a particular functionality to your website? 🤔Want to create a more engaging user experience from your brand than just displaying content on static web pages? 🤔Finding it hard as to come up with a "compelling" and a "engaging" designs and flow for your brand? 🤔 Have any API you want integrated to your designs? Name it.., I'm here to help you with anything regarding web design and development from design to trouble shooting all the errors aligned with your website to personalization of your website content and design with in a short period of time . With my expertise and knowledge, I got you covered with everything to do with web designing and development. For the past4 years, I've been building web applications for all people from individuals to businesses owners who are interested in all sorts of functionalities like E-commerce, business profiles, custom systems with custom functionalities, Custom dashboards among others. I have a very efficient workflow and process while doing all this. I have expertise in developing beautiful, professional, reliable and affordable websites I'm proficient in the following: 🌟 Languages: ✔️ HTML ✔️CSS ✔️ JavaScript ✔️ Sass ✔️ NodeJS 🌟 Frame Works ✔️ React Js ✔️ Express Js 🌟 CSS Options ✔️ Tailwind CSS ✔️ Bootstrap ✔️ Material UI ✔️ Chakra UI ✔️ Styled Components ✔️ CSS modules 🌟 Design Tools ✔️ Figma ✔️ Adobe XD 🌟Version Control ✔️ Git ✔️ GitHub ✔️ GitLab 🌟 Other Technologies ✔️ Redux ✔️ React Router ✔️ Postman ✔️ Heroku ✔️ MongoDB Here's what to expect while working with me👇: ✔️ Pixel Perfect website designs and layout. ✔️ Fully responsive websites for both Mobile and Desktop Devices. ✔️ Fully Compatible websites with all browsers like Chrome, Firefox, Microsoft Edge, etc. ✔️ Clean, editable, reusable and tested code that can be changed from time to time. ✔️ Fully tested and finished web designs and code on real devices. ✔️ Expert help on trouble shooting errors aligned with website layouts in any browser. ✔️ Quick turn around and meeting deadlines no matter the size of the project. ✔️ Effective Communication and Attention to detail on every little aspect. ✔️ Fulltime Availability. Look at some of my work in relation to web design and development as listed in the projects section. When you hire me👨‍💼, here's what we would do: 1: First, click the invite button to invite me to your job📩 2: Once there, I'll jump on a phone call with you/video call📞 or exchange ideas with you about your needs. 3: We'll go over the details, colors🎨, assets, and the entire design/look of the template, design etc., until we have reached a middle ground So, if that sounds good, click the "invite" button, and we can start right away. Take a look at my website for more information kimeramoses.com Thanks for taking time to view my profile 🤝. Cheers🙋‍♂️, Moses.
  • $20 hourly
    Lucky K.
    HTML5 Developer
    • 4.9
    • (17 jobs)
    Lucknow, UTTAR PRADESH
    vsuc_fltilesrefresh_TrophyIcon HTML5
    QA Engineering
    WordPress Theme
    I am an expert-level Magento Web - Developer looking forward to having a long-term business relationship with you by providing you with the best Magento E-Commerce Solutions. My Services Include: * Magento Extension and Module development * Magento Theming from PSDs * Magento Speed Enhancements * Magento - eBay Integration * Magento - Quickbooks Integration * Magento API Projects * Magento Commerce Enhancements * Inventory/Attribute/Category loads into Magento * E-Commerce to Magento Migration * Magento Store Maintenance, etc. * Magento AWS Server Setup Ability to understand client requirement and provide the best solution. Thanks & Regards, Lucky Khan
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