Most computer users know that a disk image in many situations is simply an irreplaceable thing, with which you can perform quite a lot of actions, including even installing operating systems or any other software. But not everyone clearly understands what it is. Further this question will be considered in more detail.
What is a disk image, and why is it needed?
Let's start with the concept itself. Apparently, there is no need to say that, based on the name of the term itself, the disk image is a copy of the optical original stored on the hard drive or removable media in the form of a single file.
But such an interpretation applies only to those cases when the copying (cloning) of the original CD / DVD media was performed. In fact, this concept has a broader interpretation, since in specialized programs images can be collected from disparate files and folders that are stored on the hard disk and have absolutely nothing to do with optical drives. In a sense, they can be compared with archives containing packed data that can be opened using specialized applications. The images themselves are used either to record their contents on optical media, or for software emulation of "iron" drives.
When using, for example, a Windows disk image (installation distribution), using a burning (burning) program like the Nero package, you can write it to optical media and then install the operating system from it. When writing to the media, it is not the image file itself that is transferred, but just its packed contents, so on the optical media you can see the files and folders that were present on the original DVD.
If we consider the disk image as a means of emulation, say, in Windows 10, when you double-click on the file in the system, a virtual drive will appear that is absolutely identical to the “iron” drive into which the disk is inserted. And the actions performed with such a drive are no different from those used for the "iron" brother.
In addition, images can even record data on the state of the hard drive or logical partition (backup) for quick recovery (including with a working operating system and with all installed programs) after unforeseen critical failures.
The most common image formats
Now a few words about the most common formats. As a universal format adopted ISO (standard 9660). And it is he who is the most common. But this absolutely does not mean that there are no others. The fact is that the software for working with images from different developers saves images in their own formats, among which the most popular are the following:
- BIN - format of PlayStation and SEGA consoles;
- MDF - Alcohol program file 120% (may contain an additional MDS file);
- IMG - an image created in the MagicISO program;
- NRG - the standard application format of the Nero package;
- CCD - copies of music tracks or data present on CD / DVD media;
- CUE - information about the tracks on the CD / DVD (metadata);
- DMG is the "apple" format of MacOS X operating systems.
Almost all programs, so to speak, by secret agreement of developers, except for their own format, are able to work with everyone else. The only exception is the DMG format, which is not recognized on Windows systems. No, you can open it with some program, but what's the point if the content is unreadable and unusable? By the way, the paradox also lies in the fact that almost all the formats presented can be unpacked in the literal sense of the word using archiver programs (for example, WinRAR), which really perceive images as archive containers with data.
Work with disk images
The applications listed above can be used to work with images. Which of these is more convenient is difficult to say.
Many users believe that creating a disk image with Windows 7 or another system is best in the Alcohol 120% application. Others recommend UltraISO, a powerful application, but, unfortunately, does not always work correctly with non-native formats other than ISO. Nero Burning ROM is a classic that has been tested for years. However, any program can read and create a disk image. You can even set the output file format yourself by refusing to use the one offered by the program when saving by default.
Instead of a total
That, in fact, is all that relates to images, their types and applications. I don’t want to recommend a specific application for work just for the reason that each user has their own preferences. Moreover, as they say, everything is known in comparison. Having tried a couple of programs in action, you can choose your preferred applet.