‘Graceful degradation’ and ‘progressive enhancement’ are terms that have crept into the web design world and I’ll admit that initially I didn’t know what they were or how they would affect the way I approach a design job, but after reading a few articles online and listening to a recent talk from Elliot Jay Stocks it proved to not just be a buzz phrase but how we as web designer should serve our users, so here is my layman’s take on both these approaches.
Graceful degradation
Graceful degradation is the creation of a web page built ideally for the latest web browsers with all the newest capabilities, then adding elements for less capable or older browsers. An obvious example of this is the use of alt tags where the text explains what the image represents but doesn’t give as good an experience as the image itself, therefore degrading the experience.
Progressive enhancement
This term seems to have been born purely for web design, progressive enhancement is the building of web pages so that all can access the information equally but those with newer technology (web browsers) may receive a richer experience during the visit. For instance the addition of certain CSS 3 selectors can be added to create effects such as round corners or other effects to a page; however, these will only be recognised by the newest browsers and will be ignored by any older or less capable versions giving those with newer browser an enhanced experience.
Strangely these both sound very similar but the user experiences will depend on the technology of your users; just take a little time before you start any project to decide how you want the experience to take place. I also don’t believe that either of these methods quite deal with all potential problems completely but they both carry the same message for me; that message is because a user doesn’t use the web the same way as you or isn’t bang up-to-date with the latest tech you shouldn’t ignore there experience, they are as important as any other user so try your best to cater for all.
As I am no expert on the intricacies of each theory here are a number of much more in-depth articles to help with your understanding of both these concepts.
http://accessites.org/site/2007/02/graceful-degradation-progressive-enhancement/
http://www.smashingmagazine.com/2009/04/22/progressive-enhancement-what-it-is-and-how-to-use-it/
http://dev.opera.com/articles/view/graceful-degradation-progressive-enhance/