High definition is the latest and best screen standard for television. It
comes in three different flavors: 720p, 1080i and 1080p. This can be confusing.
What do these standards actually mean?
High definition programs are encoded with a type of resolution: 720p, 1080i
or 1080p. The number stands for the amount of lines embedded within the signal.
The letter describes the type of scan the television uses to display the
picture. The ‘i’ means interlaced and the ‘p’ means progressive.
Do the number of lines matter?
The number of lines on a television is important because it allows for
greater detail in the image. This is a similar concept to digital photos and how
dpi determines print quality. The type of televisions all of us grew up watching
had 480 visible lines on the screen. By doubling the amount of lines in
combination with the type of scan, HD essentially doubles the quality of
Does it matter if the resolution is interlaced or progressive?
The type of scan is arguable considering the amount of lines for each HD
format. Progressive scan is a better type of scan because it doubles the amount
of times the TV displays the image per one second in comparison to interlaced.
1080p is the best resolution and is also refered to as Full HD.