Introduction to Web Accessibility
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As developers, it’s easy to assume that all users can see and use a keyboard, mouse or screen, you feel everyone can interact with your web page the same way you do. This can lead to a user experience that works well for some people but creates issues for others :(
Many developers have only a little or blurred understanding of what accessibility means, of course, accessibility can be a complex and difficult topic but understanding it, its scope and its impact can make you a better and inclusive web developer.
In this article, I’ll introduce you to accessibility, what it means, why you should care, a few tips, tools and resources to get you started.
Gif by Jona Dinges
What is Accessibility?
Let’s start by defining accessibility and inclusion.
According to thesaurus dictionary, accessibility simply means: easy to approach, reach, enter, speak with, or use.
Inclusion is a societal ideology regarding individuals with disabilities and special education. Inclusion describes a group that’s particularly welcoming to all kinds of people irrespective of their differences.
In computer-human interaction, accessibility simply means making the web accessible and having functionalities that can be operated by literally everyone including those with all forms of disabilities, limitations and conditions.
Those with Disabilities
According to WHO, there are about 285,000,000 people in the world today. Blind and visually impaired make up of the 285,000,000 people according to the World Health Organization (June 2012) with 39,000,000 categorized as legally blind and the remaining 246,000,000 visually impaired. The deaf and hearing impaired make up 275,000,000 (2004) in the moderate-to-profound hearing impairment category.
Some forms of disabilities include:
- Physical disabilities (One that affects a person’s mobility or dexterity)
- Intellectual or Learning Disabilities ( People with an intellectual, learning, or cognitive disability have a reduced capacity to read, learn tasks or process information.)
- Visual impairments (People with sight challenges, visually impaired individuals and blind people.)
- Hearing impairments ( Deafness and hearing loss)
- Neurological disabilities ( Disabilities associated with damage to the nervous system that results in the loss of some physical or mental functions.)
Those with limitations/ conditions
Disabilities can also be conditional.
- A broken arm
- A loud restaurant
- Not speaking the local language e.t.c
All these are examples where someone may benefit from accessible practices.
Everybody is a keyboard user when they are eating with their mouse hand.
— Adrian Roselli
How can we help these people?
Web Accessibility comes to the rescue. It is a practice whereby web applications are designed and developed so that its functionality can be operated by people with disabilities.
Web Accessibility Guidelines
Throughout this article, I’ll refer to the Web Content Accessibility Guidelines (WCAG) 2.0, a set of guidelines and best practices put together by web accessibility experts to address what “accessibility” means in a methodical way.
WCAG is organized around four principles often called The POUR Principle:
- Perceivable: Can users perceive the content? This ensures that our applications are perceivable with sight, touch, or hearing senses via the browser or assistive technologies e.g Screen readers
- Operable: Can users use UI components easily and navigate the content? For example, something that requires a hover interaction cannot be operated by someone who can’t use a mouse or touch screen. This means users should be able to control your web apps elements using either the mouse, keyboard or an assistive device.
- Understandable: Can users understand the content? Can users understand the interface and is it clear and concise? This ensures an easy understanding and smooth user experience.
- Robust: Can the content be consumed by a wide variety of users on several browsers? This ensures compatibility of your app across several devices, browsers or operating systems.
Web accessibility tips
Now that you understand what Web Accessibility means and why you should care, let me walk you through a few tips that would help you to build accessible websites :)
- Always add alternative texts to images
This is one thing most developers miss, I used to miss this too when I started out because I didn’t really understand the essence of alternative texts.
Alternative texts (also know as
alt) is a word that can be inserted as an attribute in an HTML document to tell your website users the contents of an image. The alt text appears in a blank box that would normally contain the image. Alt text is useful when an image is not available because of a broken link, changed URL or something else.
Alternative texts as the name imply serve as an alternative for screen readers. They are read aloud to blind users on a screen reader and otherscreen assistive technologies.
You add alternative texts to images with the
<img src="./school.png" alt="a private school in Kogi State.">
Another important aspect of the
alt attribute is that you should be specific when adding these texts. For example, examine the images below:
Beautiful Aniekan Inyang
<img src="./lady.png" alt="a beautiful lady">
<img src="./lady.png" alt="a beautiful lady smiling in front of a brown door">
Which of the code above would support accessibility more, 1 or 2?
<img src="./dog.png" alt="a cute dog">
<img src="./dog.png" alt="a cute dog sitting beside a pillow on a gray couch">
Which of the code above would support accessibility more, 1 or 2?
Now you should understand the context of being specific when using alternative texts. You might not see the need, you probably would not need it, but a whole lot of users with disabilities need it.
- Design your forms for Accessibility
Ensure you add
<label> to your form elements though they might not be visible. You can add labels for screen readers and still hide them from displaying to other users.
<form action="./contact.php" method="POST"> <label for="fullname">Full name</label> <input type="text" name="fullname" id="fullname"> <label for="email">Email address</label> <input type="email" name="email" id="email"> <label for="phone">Telephone</label> <input type="number" name="phone" id="phone"> </form>
Ensure that your
for attribute matches the
- Always specify your web app language
<html lang="en-US"> // American english
<html lang="en-UK"> // British english
<html lang="fr"> // French
If your app supports multiple languages or translations, ensure to specify that too.
- Don’t use tables for anything except tabular data
- Don’t auto-play video, music or other media files (Please avoid this)
- Ensure that links are recognizable. Either underlined or with a different colour
- Always provide a skip to main content option
Skipping to main content links are useful for users who use keyboard navigation only
<body> ... <a href="#main">Get Started</a> ... <p> Our story is a story which explains another story. Cut the crap this is too long and I don't want to read it. </p> ... <main id="main"> <!-- page specific content --> <p> Here's the main stuff bro </p> </main> </body>
- Reduce your divs and make use of semantic elements
HTML5 provides additional elements, such as
<aside>, to better structure your content.
I’d stop here as we have tons of accessibility guidelines, but don’t worry, I’ve included links for further reading below :)
The A11y project
This is a community-driven effort to make web accessibility easier with tons of resources, events, patterns, checklists and lots more to help you build more accessible applications. https://a11yproject.com/
Accessibility can be a complex and difficult topic. The Accessibility Project understands this and wants to help make it easier to implement on the web.
Web accessibility tools
This CSS file intends to warn developers about possible risks and mistakes that exist in HTML code. It can also be used to roughly evaluate a site’s quality by simply including it as an external stylesheet.
- Chrome lighthouse
Lighthouse is an open-source, automated tool for improving the quality of web pages. You can run it against any web page, public or requiring authentication. It has audits for performance, accessibility, progressive web apps, and more. Read my previous article: Introduction to chrome lighthouse to get started.
- Contrast Checker
Check the contrast of your colour design for accessibility based on Web Content Accessibility Guideline (WCAG). Check it here.
A chrome extension which is helpful for understanding the problems faced by people with slight to extreme vision problems. Download here
A full list of web accessibility tools can be found here
- Web Content Accessibility Guidelines (WCAG 2.0)
- HTML Language Codes
- Guide to using Alternative Texts on images by Egwuenu Gift
- Creating valid and accessible links
- ARIA Landmark roles and HTML5 implicit mapping
- Introduction to NDVA
- How-to hide content but still make it accessible to screen readers.
- How-to: Using caption services with HTML5 video
- Basic screen reader commands for accessibility testing
A full list of web accessibility resources can be found here
Everyone should be able to access and enjoy the web irrespective of their challenges or limitations. As developers, we’re building solutions for every user and not just some users. As much as we focus on UI/UX, we should also put extra focus on accessibility. Thanks for reading!
Nice intro! :)
Worth noting that the right content for ALT attributes varies a lot based on context. One useful guide I've heard is to use ALT to provide whatever information a sighted user might get from the image, in full context.
So your examples might be:
<img src="./lady.png" alt="Ms Aniekan Inyang"> <img src="./dog.png" alt="a cute dog sitting on a couch next to a cushion with the Google logo">
...depending on whether the lady's identity is the key point; or if the article was about dogs in Google offices.
Purely decorative images should get an empty ALT, eg. a lot of websites have banner images that add no real content at all and can be ignored by everyone including disabled users:
<img src="./generic-stock-photo.jpg" alt="">
WebAIM have a great guide on this: webaim.org/techniques/alttext