As you probably know, the aspect ratio of the monitor, that is, the width of the frame to its width is a concept widely used not only in IT, but also in cinematography, television and photography.
It was even born in these industries, even before the first displays, instead of a set of light bulbs that people used in old computers. The first displays were the first information output devices.
For computer peripherals, people use this term as one of the key parameters. This value relates to the decomposition standard and quantifies by the ratio of width to length, measured in pixels.
Monitors of the same physical size can have different resolutions and aspect ratios. You can learn more about monitor sizes from this post.

In this article, we will consider the issue in detail: find out what the main aspect ratios are, which is better for movies or games, and if this parameter really matters.
4:3
The oldest standard aspect ratio, also the standard frame size for the MPEG-2 compression algorithm. If you remember CRT monitors, you probably remember their square shape. For a square monitor, displaying old movies shot in the same aspect ratio is “native». However, when watching modern (once called “widescreen”) movies, such a monitor will have two wide black bars at the top and bottom. Stretching it distorts the picture so much, that it can hurt the aesthetic feelings of any movie buff.
Nevertheless, these monitors are still used somewhere: for example, in public institutions, not getting, necessary to update the material and technical base of the budget funds.
However, we are talking about LCD monitors – the device with this aspect ratio is widespread along with “widescreen” until the market was not finally determined in what direction to move forward.
The most common were monitors with a resolution of 1024×768 or 1600×1200, which corresponds to a ratio of 4:3. In addition, there were displays with a resolution of 1280×1024, which many users mistakenly attributed the same ratio. In fact, the ratio is slightly different – 5 to 4.
16:10
The first widescreen monitors use this ratio, as well as laptops, whose screens had a resolution of 1280×900, 1440×900 or 1680×1050. In fact, the ratio is slightly different, but companies created it just for marketing purposes (I do not agree with this).
In today’s realities, it is not as popular as aspect ratio. But they still are, used and produced in most cases, monitors c 1920 x 1200 pixels for engineers, photographers, designers (and not only), who need a large working area height.
One such instance is the Dell U2412M 24″ Black – a cool unit and not expensive for its characteristics (so I recommend it).And also want to separately note that this aspect ratio is still widely used in Apple MacBook.
16:9
The most “fashionable” and common screen format for PCs and laptops today. “Standard” today is a monitor with a diagonal of 24 inches, which has a resolution of 1920×1080, which corresponds to Full HD.
In laptops, the most common screen resolution is 1366×768 with a diagonal of 15 inches. We are talking about the average price segment: top models are equipped with large screens with high resolution.
It is this aspect ratio is oriented on Hollywood and other, not so famous studios. If you are a movie buff, then when you buy a monitor with this aspect ratio, you can watch your favorite movies without image distortion.
Keep in mind that computer services like YouTube and Twitch adopted this ration. Therefore, if you intend to start a career as a gaming blogger or streamer you need this monitor.
Otherwise, services will add vertical or horizontal bars to your videos or streams to compensate for “missing” pixels.
What does this mean in practical terms? Nothing that you should be seriously worried about, but you will get more enemies (and you will get them, do not worry) – why does that everyone broadcast “by standard”, and this upstart shows off! Their snide comments at the initial stage can once again piss you off – just until you develop immunity to any unconstructive criticism.
21:9
I want to mention+ in passing an innovative idea that failed at the implementation stage. Some manufacturers of TV sets and later monitors aggressively promoted this resolution.
This screen is best suited for watching movies made with SinemaScope technology or analogues that are more modern.

However, due to the difficulties of adapting the existing digital content, the development gradually stalled, and screens with this resolution did not get the proper distribution. The main reason is that the format was not on the list of resolutions supported by the Blu-ray Ultra HD standard. Conspiracy? Definitely, yes!
Last but not least
In terms of convenience for work and video games, there is absolutely no difference what resolution monitor you will use – it is more a matter of habit. Word documents, Excel tables, and modern games displays equally correctly on any screen size and aspect ratio.
The only exception here, perhaps, is old-school “lamp” games (for example, the third “Heroes of Sword and Magic”, which some still play), where modern monitor resolutions, in the list of supported, are absent in principle – if it is a “native” assembly, not a mod, finalized by enthusiasts.