A responsive web design, simply abbreviated as RWD refers to an approach that makes web pages open and respond well to multiple devices and windows/screen sizes.
There have been several developments in this context, adding viewer proximity as an extension. Modern internet users are looking for great content, design and performance in any device. That is why RWD focuses on to offer usability and satisfaction.
RWD helps a site adapt the layout to any viewing environment. It uses fluid, proportion-based grids and CSS3 media queries.
Many people are using mobile devices to access the internet. This makes responsive design essential in modern websites.