The hot topic for web developers and website owners is the way that websites can now automatically respond and adapt to any device with any screen size. This new way of web design optimizes the layout of the site to suit the screen size of the device it is being viewed on. There are two ways in which this can be achieved: with Responsive Web Design (RWD), coined by Ethan Marcotte, and with Adaptive Web Design (AWD), coined by Aaron Gustafson. Visitors to your site will not be concerned about which of the two methods you have used. This can simply come down to your or your designer’s preference. The user will not notice a visible difference between the two methods but they do differ slightly.
If you’re interested in the technical aspects we explain them below.
Responsive Web Design (RWD)
The key elements that make up a Responsive website are CSS3, media queries, the @media rule, and fluid grids that use percentages to create a flexible foundation. It is also fundamental to use flexible images, flexible videos, fluid type and EM’s instead of pixels. All of these key points allow the responsive website to modify its layout to suit the device.
Responsive design is client-side which means the page is sent to the device browser (the client), and the browser then modifies the appearance of the page in relation to the size of the browser window.
The definition of a responsive website is that it will fluidly alter its composition to improve the accessibility of content depending on the screen size of the browser window.
Adaptive Web Design (AWD)
Adaptive web design uses predefined layouts that have been carefully constructed for a variety of screen sizes. A particular layout is activated when the screen size of the device viewing the website is detected and matched with a style sheet.
Adaptive design is predominantly server side. This means that the web server does all of the work of detecting the various devices and loading the correct style sheet depending on the attributes of the device. As well as the layout changing depending on the size of the screen they can also change depending on conditions like whether the device has a retina display or not. The server can detect this and display high quality images for retina display devices like iPads and lower quality images for standard-definition displays.
The downsides to AWD are that initial construction is very costly as you have a lot of layouts to design. Also to maintain and update all of these layouts can be very time consuming which will therefore cost a lot of money.
The definition of an adaptive website is one that has a set of predefined layouts that are activated when best suited to the device detected by the server.
Similarities and differences
The obvious similarity of both methods is that they improve accessibility of website content on mobile devices and various screen sizes. They also both provide visitors with an enhanced mobile-friendly user experience.
They are different in the way that they deliver the responsive / adaptive design to the user. RWD is dependent on fluid grids and AWD is relying on predefined size layouts. Also the fact that they either use client side or server side is another way in which they differ.
The visible difference is that responsive design will fluidly alter its layout while you resize your browser window whilst adaptive design will load a specific layout for the device you’re viewing the site on. If you resize your window with an adaptive website it will jump to a different breakpoint when you reach a screen size that suits another predefined layout.