Web Standards and Accessibility: A Brief History
How the W3C, HTML and CSS standards and the WCAG accessibility guidelines developed, and why they matter for every business website.
How to Redesign a Website · Last reviewed October 19, 2026 · 5 min read
When you build a website, you are relying on a quiet agreement between thousands of companies and people around the world. Your page is written in a shared language, and browsers made by different companies all agree on how to read it. That agreement is what we call web standards, and without it the web would splinter into incompatible pieces.
Alongside standards for how the web works, another set of guidelines grew up around who the web works for. Web accessibility means making sites usable by people with disabilities, including people who are blind or have low vision, are deaf, have limited movement, or have cognitive differences. The history of both shows how the web became more reliable and more inclusive, and why both matter for any business website today.
Why the Web Needed Standards
In the early 1990s, the web's technologies were defined largely by its inventor, Tim Berners-Lee, and the small team around him at CERN. As browsers multiplied and companies began competing, there was a real risk that each would invent its own version of the web.
To prevent that, Berners-Lee founded the World Wide Web Consortium, or W3C, at the Massachusetts Institute of Technology in October 1994, in collaboration with CERN and with support from the US defence research agency DARPA and the European Commission. Inria in France became a host in 1995, followed by Keio University in Japan in 1996. In 2023, the W3C reorganized as an independent public-interest non-profit organization. Its job, then and now, is to bring companies and experts together to agree on open standards that anyone can use.
HTML Grows Up
HTML, the language web pages are written in, has gone through several formal versions:
- HTML 2.0 was published as an internet standards document, RFC 1866, in November 1995.
- HTML 3.2 became a W3C Recommendation on January 14, 1997.
- HTML 4.0 followed in December 1997, and the widely used HTML 4.01 in December 1999.
- XHTML 1.0, a stricter reformulation of HTML 4, became a Recommendation in January 2000.
In the early 2000s the W3C focused heavily on XHTML and its successors. Some browser makers felt this ignored the needs of everyday web developers. In 2004, people from Apple, Mozilla and Opera founded the Web Hypertext Application Technology Working Group, or WHATWG, to evolve HTML in a more practical direction. Their work became the basis of HTML5, which the W3C published as a Recommendation on October 28, 2014.
For several years, the W3C and WHATWG maintained separate versions of HTML, which was confusing. On May 28, 2019 they signed an agreement to work together on a single version. Today the WHATWG maintains the HTML Living Standard, a continuously updated specification rather than a series of numbered releases.
CSS: Standards for Style
CSS, or Cascading Style Sheets, controls how pages look: fonts, colors, spacing and layout. The W3C published CSS level 1 as a Recommendation on December 17, 1996 and CSS level 2 on May 12, 1998. Since then, CSS has grown as a set of separate modules, each covering a feature such as layout, color or animation, so improvements can arrive piece by piece rather than in one giant release.
Browser support for these standards was uneven for years, especially during the browser wars. Groups such as the Web Standards Project, formed in 1998, campaigned for browser makers to support W3C standards fully, and over time they largely did.
Accessibility Joins the Story
On April 7, 1997, the W3C launched the Web Accessibility Initiative (WAI) to promote web access for people with disabilities. Announcing it, Berners-Lee said that "it is critical that the Web be usable by anyone, regardless of individual capabilities and disabilities."
The WAI's best-known work is the Web Content Accessibility Guidelines, or WCAG:
- WCAG 1.0 became a W3C Recommendation on May 5, 1999.
- WCAG 2.0 followed on December 11, 2008. It was designed to be more testable and less tied to specific technologies.
- WCAG 2.1 was published on June 5, 2018, adding 17 success criteria to better address mobile accessibility, people with low vision, and people with cognitive and learning disabilities.
- WCAG 2.2 was published on October 5, 2023, adding nine more success criteria, and was updated in December 2024. The W3C notes that WCAG 2.2 is also an approved international standard, ISO/IEC 40500:2025.
WCAG 2 is organized around four principles: content should be perceivable, operable, understandable and robust. Each guideline has testable success criteria at three levels, A, AA and AAA. Many organisations and laws use level AA as their benchmark. A new generation, WCAG 3, is under development as a draft.
A Short Timeline
- October 1994: The W3C is founded at MIT.
- November 1995: HTML 2.0 is published.
- December 1996: CSS level 1 becomes a W3C Recommendation.
- April 1997: The W3C launches the Web Accessibility Initiative.
- May 1999: WCAG 1.0 is published.
- 2004: The WHATWG is founded.
- December 2008: WCAG 2.0 is published.
- October 2014: HTML5 becomes a W3C Recommendation.
- June 2018: WCAG 2.1 is published.
- May 2019: The W3C and WHATWG agree on a single HTML standard.
- October 2023: WCAG 2.2 is published.
Why Standards and Accessibility Matter for Your Website
Standards are the reason a well-built website works in Chrome, Safari, Edge and Firefox, on a phone or a laptop, without separate versions for each. Sites built on standards also tend to last longer, because browsers work hard to keep supporting them, while sites built on proprietary technologies such as old plugins can stop working entirely.
Accessibility matters for people first: an inaccessible site shuts out customers who want to buy from you. Many of the same practices also make a site easier for everyone to use, such as clear headings, readable text, descriptive links, captions on videos and forms that work with a keyboard. In many countries, accessibility is also a legal consideration, so it is worth asking any web designer how they test against WCAG.
When planning a redesign, ask for clean, standards-based code and a target of WCAG 2.2 level AA. Those two requests cover a great deal of what makes a website reliable, inclusive and future-proof.
Key takeaways
- The W3C was founded in October 1994 to keep the web open and built on shared standards.
- HTML evolved through numbered versions to today's HTML Living Standard, maintained by the WHATWG since a 2019 agreement with the W3C.
- The W3C launched its Web Accessibility Initiative in 1997, and WCAG has evolved from 1.0 (1999) to 2.2 (2023).
- Building to standards and to WCAG level AA makes a website work across browsers and for more people.
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