1080i is the shorthand name of high-definition video mode. The number 1080 stands for number of horizontal lines - vertical resolution, and letter i stands form interlaced. 1080i is known as high-definition television (HDTV) video mode with widescreen aspect ratio of 16:9 and a frame resolution of 1920 × 1080.

Interlaced scanning means that the picture is formed on the screen by scanning in two consecutive passes where odd numbered lines are displayed in one pass, and the even numbered lines in the pass that follows. 1080i is compatible with newer 720p and 1080p based televisions.