HTML5 Interview Masterclass

50 Essential Questions for Professional Developers

HTML (HyperText Markup Language) is the standard markup language used to create the basic structure of a website.

Tags that describe their meaning (e.g., <header>, <article>, <footer>). They improve SEO and accessibility.

It informs the browser about the HTML version (HTML5) to ensure consistent rendering.

Div is a block-level element (takes full width), while Span is an inline element (takes only content width).

Elements without a closing tag, like <br>, <img>, and <hr>.

Alternative text for an image if it fails to load; vital for Screen Readers.

It provides a drawable region in JS for rendering graphs, game graphics, or visuals on the fly.

Used to embed another HTML page inside the current one.

LocalStorage persists data after browser closing; SessionStorage clears when the tab is closed.

Snippet of text that describes a page's content; they don't appear on the page but in the code.

Use the attribute target="_blank" inside the anchor tag.

It represents the dominant content of the <body> of a document.

Scalable Vector Graphics. It is an XML-based format for 2D vector graphics.

A thematic grouping of content, typically with a heading.

Using the <video> tag with <source> and controls attribute.

Using the <audio> tag with <source> and controls attribute.

Used for content indirectly related to main content, like sidebars or call-out boxes.

A section of a page that links to other pages or parts within the page.

Ensures the website is responsive and fits the screen of mobile devices.

<b> is for styling (bold); <strong> implies semantic importance/urgency.

An element used to collect user input that is typically sent to a server.

Appends form data to the URL; used for non-sensitive data like search queries.

Sends data in the HTTP request body; used for sensitive data like passwords.

A hint or example text shown inside an input before the user types.

Allows a user to select only one option from a predefined set of choices.

Allows a user to select multiple options from a set of choices.

Defines a label for an <input> element, making it easier to click and accessible for screen readers.

Used for multi-line user input, like comments or messages.

Prevents form submission if the input field is empty.

Used to create a drop-down list of options.

Table Row (tr), Table Data (td), and Table Header (th).

Used to merge multiple table columns into one cell.

Used to merge multiple table rows into one cell.

Unordered List (bullet points) vs. Ordered List (numbered/alphabetical).

Description List, used for terms (<dt>) and descriptions (<dd>).

Codes used to display reserved characters like &copy; (©) or &lt; (<).

Used to group media content (like images) with a caption (<figcaption>).

Contains metadata, links to stylesheets, scripts, and the page title.

Contains the bottom section of a page or section, often with copyright and links.

Using <link rel="icon" href="favicon.ico"> in the <head>.

JavaScript running in the background, independently of other scripts, to keep pages responsive.

SVG is vector-based (scalable); Canvas is pixel-based (raster). SVG is better for icons; Canvas for games.

Used to store custom data private to the page or application.

Displays a progress bar representing the completion of a task.

Represents a scalar measurement within a known range (like disk space).

Ensures all symbols and characters are displayed correctly on all browsers.

Consists of LocalStorage and SessionStorage to store data on the client side.

The <button> tag allows HTML content inside (icons), whereas <input> is value-only.

Add the disabled attribute to the element.

Used to create a native toggle or accordion without needing JavaScript.