Accessibility was unfortunately not a primary consideration of most early web design. This is perhaps ironic, as the one of Berners-Lee’s design principles in creating HTML was that information was that things were to be tagged semantically (<em> and <strong> ) rather than styled (<b> and <i>). Semantic markup allows browsers to display material in a way appropriate to the limitations of software and hardware or according to user preference. For example, a browser designed for a monochrome monitor would choose some formatting other than color to indicate hyperlinks. The rejection of Berners-Lee’s semantic markup perhaps reached its apex with the introduction of the infamous <blink> tag in the mid 1990’s. Not surprisingly, although standard bodies such as W3C have created guidelines, much of the improvement in web accessibility has been driven by government regulation of both government websites and those produced by entities receiving government funding.
While accessibility is an ongoing process, there are a few aspects that should be a high priority , because of their frequency in web design:
ALT-Text – Since NCSA Mozilla, the web has been a visual medium. A page filled with only text comes across as quaint and even retro. However, this means that images need text descriptions. The HTML standard addresses this with the <img> tag alt attribute, if designers take the time to use it. See below for a site with do’s and don’ts for writing good ALT text.
Color choices – There are many ways to combine colors on a web page. Some of them are not effective. Beyond the difficulty caused by low contrast pairings (such as a pale pastel on white), there are five different kinds of color vision deficiency (see Resources below). Put that all together and you have several ways you can make your site difficult for some of your users to read.
Transcripts / captions – If your web site includes audio and/or video, transcripts and/or captions are important for any users who might have a hearing disability. The general advice to write a script is helpful, as this should end up being very close to your transcript. Auto-captioning/ transcripting is improving, but you still need to review and correct the output before adding it to your media.
Resources
- Guidance on Web Accessibility and the ADA
- https://www.ada.gov/resources/web-guidance/
- This site, from the USDOJ, provides a detailed overview of web accessibility requirements which derive from the Americans with Disabilities Act
- Harvard Digital Accessibility Alt-Text guidelines.
- https://accessibility.huit.harvard.edu/describe-content-images
- This page provides helpful suggestions on how to make your ALT text useful for your site’s visitors.
- WAVE
- htttp://wave.webaim.org
- This suite of tools, from Utah State University , helps web designers test for accessibility.
- Types of color vision deficiency
- https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/color-blindness/types-color-vision-deficiency
- This page, from the US National Institutes of Health , describes categories and types of color vision deficiency.
- European Commission Web Accessibility Resources
- https://commission.europa.eu/resources-partners/europa-web-guide/design-content-and-development/accessibility/testing-early-and-regularly_en
- While US developers will naturally focus on US legal requirements , the web is a global medium and it’s wise to be aware of requirements wherever your users might be.