Web Extras

What is the latest version of HTML?

HTML 5.2, published by the World Wide Web Consortium (W3C) on December 14, 2017 [32], is the last finalized version of HTML released as a W3C Recommendation. Work on HTML 5.3 began afterward, but it was never completed or officially released. As a result, there is no official “next version” of HTML, such as HTML 6, and HTML 5.2 remains the latest formal snapshot by the W3C.

The responsibility for maintaining the HTML specification has shifted from W3C to the Web Hypertext Application Technology Working Group (WHATWG), a consortium formed by leading browser companies, including Apple, Google, Mozilla, and Microsoft [32]. WHATWG introduced the concept of the HTML Living Standard, which is continuously updated to reflect the latest features, improvements, and browser implementations.

In May 2019, W3C and WHATWG signed a Memorandum of Understanding (MOU) to collaborate on a single version of the HTML and DOM specifications. This agreement formalized the transition: W3C no longer independently publishes HTML standards and instead works to bring WHATWG Review Drafts to W3C Recommendations. As part of this collaboration, W3C retired its HTML specifications, including HTML 5.2, on January 28, 2021, in favor of the continuously evolving HTML Living Standard maintained by WHATWG [33].

What are CSS rules and how do they work?

CSS rules determine how web page elements are presented and structured. Broadly, all CSS rules can be classified into two main categories:

• Style rules: the standard rules most commonly used in CSS. They consist of a selector, which identifies the HTML element(s) to be styled, and a declaration block, which defines the properties and values.
  

  Example:

    p {
      color: blue;
      font-size: 16px;
    } 
              

  This rule sets the text color to blue and the font size to 16 pixels for all elements. Style rules also follow the concept of specificity, which determines which rules take precedence when multiple rules target the same element. Understanding specificity is essential for avoiding conflicts and ensuring the intended styles are applied.

• At-rules: special instructions that start with the @ symbol and extend CSS beyond basic styling, such as including external stylesheets, applying conditional rules, or defining animations. Key examples include:
  • @import: allows including external style sheets. This promotes modular and reusable CSS, though excessive use can slow page loading.
  • @media: applies styles conditionally based on device characteristics, such as screen size or orientation, enabling responsive design across desktops, tablets, and mobile devices.
  • @font-face: lets designers embed custom fonts for consistent typography across platforms.
  • @keyframes: defines animations by specifying how element styles change over time.
  • @supports: applies styles only if the browser supports certain CSS features, enhancing compatibility.
  • @layer: introduced recently to control the cascade and prioritize certain sets of styles, improving maintainability of complex CSS [34].

  At-rules give developers greater control over styling behavior, resource management, and interactivity. While style rules determine how elements look, at-rules dictate when, how, or from where styles are applied, significantly expanding the flexibility and power of CSS.