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Common display resolutions are 144p, 240p, 360p, 480p, 720p, 1080p, 1440p, and 2160p. For example, these are the resolutions that YouTube offers. These are somewhat odd numbers and I cannot find a pattern. I tried searching but could not find the reason why these resolutions were chosen and became standards.

This query is different from this one which inquires about physical screen sizes but it is similar in spirit.

Does anybody know why common display resolutions are the way they are?

16:9 Aspect Ratio

The pattern you're referring to is the 16:9 aspect ratio. @Worthwelle's comment is correct 16:9 replaced 4:3 aspect ratio.

16:9 (1.77:1) (16:9 = 42:32) is an aspect ratio with a width of 16
units and height of 9. Since 2010 it has become the most common aspect
ratio for televisions and computer monitors, and is also the
international standard format of HDTV, Full HD, non-HD digital
television and analog widescreen television. This has replaced the old
4:3 aspect ratio.

16:9 aspect ratio

The reason why the aspect ratio has become the standard can also be attributed to the DVD format.

16:9 is the only widescreen aspect ratio natively supported by the DVD format. Anamorphic DVD transfers store the information as 5:4 (PAL) or 3:2 (NTSC) square pixels, which is set to expand to either 16:9 or 4:3, which the television or video player handles. For example, a PAL DVD with a full frame image may contain a video resolution of 720×576 (5:4 ratio), but a video player software will stretch this to 1024×576 square pixels with a 16:9 flag in order to recreate the correct aspect ratio.

DVD producers can also choose to show even wider ratios such as 1.85:1 and 2.39:1[a] within the 16:9 DVD frame by hard matting or adding black bars within the image itself. Some films which were made in a 1.85:1 aspect ratio, such as the U.S.-Italian co-production Man of La Mancha and Kenneth Branagh's Much Ado About Nothing, fit quite comfortably onto a 1.77:1 HDTV screen and have been issued as an enhanced version on DVD without the black bars. Many digital video cameras have the capability to record in 16:9.

16:9 Properties

List of standardised 16:9 resolutions

• 256 x 144 YouTube 144p


• 640 x 360 nHD


• 960 x 540 qHD


• 1280 x 720 HD
  


• 1366 x 768 WXGA
  


• 1600 x 900 HD+


• 1920 x 1080 Full HD
  


• 2560 x 1440 QHD
  


• 3200 x 1800 QHD+


• 3840 x 2160 4K UHD
  


• 4096 x 2304 Full 4K HD


• 5120 x 2880 5K UHD
  


• 7680 x 4320 8K UHD
  

These are somewhat odd numbers and I cannot find a pattern.

They are not actually random but based on actual industry standards. Low-definition defines anything that is below Standard-definition. Standard-definition and Enhanced-definition take care of resolutions below 576p and below. While High-definition and Ultra High-definition take cares of resolutions between 720p and 8k. In all cases, we are actually talking about television standards, but the same standards are applicable to the resolution on a computer monitor.

Low-definition television (LDTV) refers to television systems that
have a lower screen resolution than standard-definition television
systems. The term is usually used in reference to digital television,
in particular when broadcasting at the same (or similar) resolution as
low-definition analog TV systems. Mobile DTV systems usually transmit
in low definition, as do all slow-scan TV systems.

Low-definition television

Standard-definition television (SDTV or SD) is a television system
which uses a resolution that is not considered to be either high or
enhanced definition. The two common SDTV signal types are 576i, with
576 interlaced lines of resolution, derived from the
European-developed PAL and SECAM systems; 480i based on the American
NTSC system. SDTV and high-definition television (HDTV) are the two
categories of display formats for digital television (DTV)
transmissions.

Standard-definition television

and

Enhanced-definition television or extended-definition television
(EDTV) is an American Consumer Electronics Association (CEA) marketing
shorthand term for certain digital television (DTV) formats and
devices. Specifically, this term defines formats that deliver a
picture superior to that of standard-definition television (SDTV) but
not as detailed as high-definition television (HDTV).

Enhanced-definition television

High-definition television (HDTV) is a television system providing an
image resolution that is of substantially higher resolution than that
of standard-definition television. This can be either analog or
digital. HDTV is the current standard video format used in most
broadcasts: terrestrial broadcast television, cable television,
satellite television, Blu-rays, and streaming video.

High-definition television

Ultra-high-definition television (also known as Ultra HD television,
Ultra HD, UHDTV, UHD, and Super Hi-Vision) today includes 4K UHD and 8K
UHD, which are two digital video formats with an aspect ratio of 16:9.
These were first proposed by NHK Science & Technology Research
Laboratories and later defined and approved by the International
Telecommunication Union (ITU).

Ultra-high-definition television

In most cases, the standards used by the television industry were defined by research, industry or consumer groups. In cases like PAL or NTSC they were chosen by the respective industry groups in the applicable region. Due to the respective choice to implement either NTSC or PAL drove future changes resolution standards.

In the case of an aspect ratio of a given resolution standard is was based on actual science.

The eye's perception of display resolution can be affected by a number
of factors – see image resolution and optical resolution. One factor
is the display screen's rectangular shape, which is expressed as the
ratio of the physical picture width to the physical picture height.
This is known as the aspect ratio. A screen's physical aspect ratio
and the individual pixels' aspect ratio may not necessarily be the
same. An array of 1280 × 720 on a 16:9 display has square pixels, but
an array of 1024 × 768 on a 16:9 display has oblong pixels.

An example of pixel shape affecting "resolution" or perceived
sharpness: displaying more information in a smaller area using a
higher resolution makes the image much clearer or "sharper". However,
most recent screen technologies are fixed at a certain resolution;
making the resolution lower on these kinds of screens will greatly
decrease sharpness, as an interpolation process is used to "fix" the
non-native resolution input into the display's native resolution
output.

Display resolution

IBM, NEC Home Electronics, and the Video Electronics Standards Association (VESA) also had an influence on what a given resolution would be defined as. While broadcast television had a huge influence, every standard resolution has it's own computer display standard also.