Responsive web design is the method used to allow web content to be viewable on multiple devices. The code used to build the site adapts to different screen sizes so that no matter which device you view a particular web site on, you are presented with a user friendly experience and engaging content.
The technology is actually not new, but the application has become more important as more and more users are accessing the web using smartphones and tablets. Using responsive web design is not the same as building unique sites for different devices. You are actually building one site, but coding it in such a way that it is delivered differently across different devices.
Mobile device usage has skyrocketed and consumers are using mobile devices even when they are at home. More than 60% of consumers make MOBILE purchases from home(Ipsos and Paypal, 2011) and 86% use their mobile devices when watching TV (Yahoo, 2011.) Clearly, creating a good user experience for these users is something to be paid attention to.
So, how do you plan for responsive web design? Many designers recommend a "Mobile First" approach. With a mobile first approach, you determine what content is the most important and will help you with your main objectives for the site first. You start with a site plan for the smallest mobile device and work your way up from there taking into consideration what a mobile user might want first and foremost. Another consideration is the load time. This plan of attack will give you the "leanest and meanest" of your web site content.
As you plan for larger devices, you can determine if there is other content that want to include in the user experience and how users of those devices might interact with your site.
There may be pros and cons to building a web presence using responsive web design. For example, you're making some assumptions about how users will interact with your content rather than allowing them to make the decision on their own. There's also the cost factor. Building a site using responsive web design is more costly than building separate sites for mobile devices. And sites using responsive design may take longer to load than a site built specifically for a single device.
Whether responsive web design should be a strategy for your business really depends on your users and the main goals of your web site. But, it is something that should be part of the web marketers toolkit when planning a strategy.