Probably, there is no such user of the Windows operating system who at least once has not wondered “What is DirectX?”. The answer to it is both simple and complex. It all depends on which side to look at: a simple user or a programmer.
In order to nevertheless understand what DirectX is, we mentally take a short excursion into the past or, more precisely, during the glorious times of the reign of the DOS system (MS-DOS). These are now serious technological breakthroughs in the field of computer technology are quite rare. Obviously, an extensive development path is currently prevailing , when the number of cores in the central processors is increased, they offer Slay (SLI) systems for video, Raid for disks and multi-channel access to RAM. When choosing a monitor or video card, no one is now interested in what standard they are.
A dozen or two years ago, everything was different: there were monitors CGA, EGA, VGA and even Tandy c Hercules. The video cards did not lag behind them. And the sound solutions were very different: Sound Blaster, Covox, PC Speaker, etc. Now imagine a programmer who decided to write a program. Since work with computer components was carried out by directly accessing the desired addresses, he had to provide for all possible combinations of components. The work was still the same, although with successful execution the program performance became enormous.
At the same time, the Win 95 system appeared, and its creators seriously thought about ways to popularize it. Due to the nature of the kernel, direct work with addresses (as it was in DOS) has become impossible. So we come to what DirectX is. Programmers were offered a unique tool - DirectX. This is a set of system libraries (files) designed to provide interaction with equipment. Now the program does not need to determine which video card is installed on the computer - it is enough to set a command using a specific call, and if the operating system can work with it, the application will receive the requested access. That is, in order to display a point on the screen, you do not need to know the programming features of this video adapter, but simply by DirectX rules indicate "display the point by coordinates." Anyone who is interested in what DirectX is, knows that the libraries (APIs) are intended to be divided into Direct3D, DirectDraw, DirectSound, etc. In addition, there are different versions: from 1 to 11.1, and, importantly, they are compatible from top to bottom.
The question “How to install DirectX 11?” Is often asked. This version is one of the latest. Installed by default in Win Vista SP2 and higher. The latest Win 8 already comes with 11.1. Installation in Win XP is officially impossible, although there are rumors of successful partial adaptation. If the message “An internal DirectX system error has occurred” appears or the game does not start, you can try updating the installed version of DirectX. To do this, it is recommended that you proceed as follows: go to the Microsoft website in the download section, type “DirectX” in the search bar, download a small file for the desired version (about 300 Kb) and run it. Missing files will be automatically downloaded and installed.
You can determine the version used as follows: open the Start menu, type Dxdiag in the search bar and press Enter. All the necessary data will be listed in the window that appears. Fans of modern games can be advised to install Seven or even Win 8 - they support DirectX 11 out of the box.
The fair question is - why do we need new versions? Imagine a situation where a programmer, for example, gives a command in an application to the API libraries “draw a light blue oval”. It will be fulfilled when two requirements are met: the video card understands this command, it is registered in the DirectX version. If everything is clear with the hardware component (indicated on the box), then the second point requires explanation. The command “draw a light blue oval” can only be supported in version 11, and in 10 two commands are required to form such an image: “draw a light blue circle and stretch it to an oval”. So simple.