Now a days where technology changes rapidly and every now and than a new device comes up with new resolution, and practically it is not possible to keep en number of website for en number of devices. Almost every customer need a web site version very flexible and compatible. He would like to access website on his device as available. So we are in need of a single web site for multiple devices.
Responsive website mean a web site is optimally compatible to various devices. Responsive website layout changes according to size & resolution of device eg. PC, tab, mobile. So you do not need any other domain URL or sub- domain to redirect as per device. The practice consists of a mix of flexible grids and layouts, images and an intelligent use of CSS media queries. As the user switches from their laptop to mobile, the website should automatically switch to accommodate for resolution, image size and scripting abilities.