What is Viewport?
Now a days Smart Phones have very High Display Resolution, A small 6-inch device have same display dimensions which a 32-inch LCD have, How it is possible?
Device Dimensions which is also known as resolution is based upon Pixel Per Inch. The devices which have higher resolution in small display, their ONE pixel contains many more pixels, thats why Retina Display or Device Dimensions got bigger. However device actual dimensions depends on actual Pixels Per Inch which is called "Viewport Size" of device or "device-width". Responsive Websites CSS styles are based upon Viewport sizes of devices. Below is a detailed comparison list of Viewport Size for devices, Phone Dimensions, Screen Sizes and Devices Resolution:
