Support the Past, Optimize for the Future
Back in middle school, I wrote every paper in Word for MS-DOS. It was a piece of software that did one thing really well: It allowed the user to focus on writing.11 You didn’t have a whole lot of options for formatting text, but it did what it needed to do, and it did it with aplomb.
More than two decades later, it’s next to impossible for me to read the DOC files Word created for me. As an application, Word long abandoned support for reading and editing that generation of the DOC format.
Now I’m not saying that the stuff I wrote in middle school is really worth reading today (I’m sure it’s not), but I am only one of millions of people who authored content in Word for DOS. That content is largely lost to history because the format evolved in a way that made newer versions of Word incapable of reading those older files.
This is a huge challenge for archivists because even if they manage to hang on to a copy of the programs that originally authored these files, they also need to maintain machines capable of running the software (which is equally challenging).
When he conceived of the World Wide Web, Sir Tim Berners Lee wanted to avoid this problem. He wanted content on the Web to be robust and future-proof, so he made that a guiding principle of the web’s lingua franca, HTML. To wit, the HTML 2.0 spec says this:12
- To facilitate experimentation and interoperability between implementations of various versions of HTML, the installed base of HTML user agents supports a superset of the HTML 2.0 language by reducing it to HTML 2.0: markup in the form of a start-tag or end-tag, whose generic identifier is not declared is mapped to nothing during tokenization. Undeclared attributes are treated similarly. The entire attribute specification of an unknown attribute (i.e., the unknown attribute and its value, if any) should be ignored.
In other words, browsers are instructed to ignore what they don’t understand. This is fault tolerance (another carry-over term from the world of engineering), and it’s central to the design of HTML as a language and CSS as well.13
Both languages were designed to be “forward compatible,” meaning everything you write today will work tomorrow and next year and in ten years. These languages were designed to evolve over time. By ignoring anything they don’t understand, browsers give these languages room to grow and adapt without ever reaching a point where the content they encapsulate and style would no longer be readable or run the risk of causing a browser to crash.
Fault tolerance makes it possible to browse an HTML5-driven website in Lynx and allows you to experiment with CSS3 features without worrying about breaking Internet Explorer 6. Understanding fault tolerance is the key to understanding progressive enhancement. Fault tolerance is the reason progressive enhancement works and makes it possible to ensure all content delivered on the Web is accessible and available to everyone.
Maintaining Your Sanity
Trying to give everyone the same experience across the myriad device and browser combinations, especially considering the variety of human factors that affect how they interact with a page, would be a fool’s errand. It’s important to pick your battles. Web developer Brad Frost beautifully couched this approach as “support vs. optimization.”
- Unless you want to hole yourself up in a cabin for the foreseeable future, you’re not going to be able to optimize your web experience for every single browser. What I’m really asking for here is consideration.
- You don’t have to treat these browsers as equals to iOS and Android and no one is recommending that we have to serve up a crappy WAP site to the best smartphones on the market. It’s just about being more considerate and giving these people who want to interact with your site a functional experience. That requires removing comfortable assumptions about support and accounting for different use cases. There are ways to support lesser platforms while still optimizing for the best of the best.14
By following this approach, you enable your content to go as far as possible, unencumbered by the requirements of some particular technology or capability. You can do this rather easily by focusing on the content and building up the experience, layer by layer, because the browser and device can adequately support that experience.
Progressive enhancement isn’t about browsers or devices or technologies. It’s about crafting experiences that serve your users by giving them access to content without technological restrictions. Progressive enhancement doesn’t require that you provide the same experience to every user, nor does it preclude you from using the latest and greatest technologies; it simply asks that you honor your site’s purpose and respect your users by applying technologies in an intelligent way, layer upon layer, to craft an amazing experience.
Browsers, devices, and technologies will come and go. Marrying progressive enhancement with your desire to be innovative and do incredible things is entirely possible—as long as you’re smart about your choices and don’t allow yourself to be so distracted by the shiny and new that you lose sight of your site’s purpose or your users’ needs.