Responsive website design is an approach to web design which makes web pages on a variety of device and window on screen size. Because content design and performance are necessary across all device to ensure usability and satisfaction. There is a wide variety of information on responsive web design all over the internet. A site designed with RWD adapts the layout to the viewing environment by using fluid, proportion based grids, flexible images and media queries.

FLUID IMAGES: Fluid images means page element sizing to be in relative units likes percentage, rather than absolute units likes pixels or point.

FLEXIBLE IMAGES: Flexible images are also size in relevant unit so as to prevent them from displaying out their containing element.

MEDIA QUERIES: Media queries allow the page to use different CSS style rules based on characteristic of the device the site is being displayed on most commonly the width of the browser.

In short we can say that the website should have the technology to automatically respond to the user preferences. This would eliminate the need for a different design and development phase for each new gadget on the market. It not only about adjustable screen resolution and automatically resizable images but rather about a whole new way of thinking design for extreme size change we may want to change the layout through a spread style sheet or more efficiently through a CSS MEDIA QUERY.