What is the resolution for high definition?

There are several resolutions that are classed as HD: 1920 x 1080 is the most common resolution. 1280 x 720 is also common and used more for sport and fast action content than other types of program. Additionally, there is a 1035 line format. Although it is a full HD format, it is no longer used but some equipment will support it.

In the case of 1080 line resolution, it can be an interlaced or progressive signal. If it is interlaced, the whole image is built from two fields with the first showing odd numbered lines and the second showing even numbered lines. Progressive scanning creates a complete picture in a single pass. As twice the number of lines are refreshed in any given time, a progressive scan demands twice the data rate of an interlaced scan. Broadcasters are not currently using 1080p as a broadcast format which currently is only found in local sources such as Bluray and games consoles.