Do you know : 720p/1080p Means what ??

720p/1080p and similar others are resolution formats that you often find in video sharing sites, in TV advertisements or in video cameras.  Here is a quick explanation for what it means.
720p means that the screen has 720 horizontal lines and 1280 vertical lines. In other words it has a resolution of 1280 x 720. Similarly 1080p has a resolution  of 1920 x 1080. Both have an aspect ratio of 16:9, also known as widescreen. 720p and 1080p are usually advertised as HD and Full HD respectively in media. We also have 480p, known as Standard Definition (SD),  which has a resolution of 640 X 480 and an aspect ratio of 4:3.


So what does the ‘p’ stands for? Well the ‘p’ stands for progressive. We also have interlaced video denoted by ‘i’. Progressive means that each line in the image is built from top to bottom in each frame of the video. While in interlaced only half on the image, i.e. each alternate line is built in one frame and and the rest in others. For eg. if we have a video with 60 frames per second (fps) then in progressive each line would be built 60 times per second while in interlaced each line would be built only 30 times.


Since interlaced displays only half of the picture in one frame, hence pictures often appear jagged or smeared especially in videos with fast action where the picture changes constantly. The progressive format is of course the dominating format today because it provides smoother and clearer pictures.  The only advantage of interlaced is that it requires less space and bandwidth to store and transmit a video of same resolution and frame rates than progressive ones.