What is the difference between 1080i and 1080p?

HDTV 1080i is an interlaced picture and 1080p is progressive. HDTV 1080p is the shorthand name for a category of video modes. The number 1080 represents 1,080 lines of vertical resolution[1], while the letter p stands for progressive scan or non-interlaced. 1080p is considered an HDTV video mode. The term usually assumes a widescreen aspect ratio of 16:9, implying a horizontal (display) resolution of 1920 dots across and a frame resolution of 1920 × 1080 or exactly 2,073,600 pixels. The frame rate in hertz can be either implied by the context or specified after the letter p (such as 1080p30, meaning 30 frames per second). 1080p is sometimes referred to in marketing materials as "True High-Definition" or "Full High-Definition". Although 2K/4K digital cinema technology is commercially available, and ultra-high definition video is in the research phase, 1080p and 1080i are currently the highest-resolution formats widely used for broadcasting and consumer distribution of video content. 1080i (pronounced "ten eighty I") is shorthand name for a category of video modes. The number 1080 stands for 1080 lines of vertical resolution, while the letter i stands for interlaced or non-progressive scan. 1080i is considered to be an HDTV video mode. The term usually assumes a widescreen aspect ratio of 16:9, implying a horizontal resolution of 1920 pixels and a frame resolution of 1920 × 1080 or about 2.07 million pixels. The frame rate in hertz can be either implied by the context or specified after the letter i. The two frame rates in common use are 25 and 30 Hz, with the former (1080i25) generally being used in traditional PAL and SECAM countries (Europe, Australia, much of Asia, Africa), the latter (1080i30) in traditional NTSC countries (e.g. United States, Canada and Japan). Both variants can be transported by both major digital television formats, ATSC and DVB. 1080i vs 1080p To compare 1080i and 1080p it is important to compare framerates. Due to interlacing 1080i has twice the frame-rate but half the resolution of a 1080p signal using the same bandwidth. This is especially useful in sport-shows and other shows with fast-moving action. However, on some flat screens that don't support interlacing, this instead becomes smeared or jarred artifacts. Current digital television broadcast systems and standards are not equipped for 1080p50/60 transmission. Also, the majority of consumer televisions offered for sale are currently not equipped to receive or decode a 1080p signal at any frequency. It is less bandwidth-intensive to broadcast a film at 1080p24 than 1080i30, since 20% less data would be transferred. In addition, when the source material is 24 frames per second, as are most films, it would be easy to convert a 1080p24 broadcast to an NTSC 1080i30 format using a 3:2 pulldown process (see telecine). Moreover, displaying a p24 broadcast on an i50 system (such as PAL) requires the speed of video and audio be increased by over 4% (to 25 frames per second). For movies the frames (25 or 30 per second) are segmented into two interlaced fields with equal time index (psf, progressive in or with segmented frames). The deinterlacer has to perform a simple weave only. This ensures compatibility with 1080i25/30 with only little less coding efficiency than 1080p25/30 and half the bandwidth requirement of 1080p50/60, but the SDTV problems of PAL speed-up and Telecine judder remain. 1080i is better