What is a disk? Computer for beginners

Solid-state storage media gradually displaces laser and magnetic disks from everyday life. Nevertheless, this will not happen soon enough. The article describes the types of computer disks.

What is a disk?

Disks have long and firmly entered our lives. But most of us are faced with CDs, and that there are other kinds of them, even have no idea. So what are they, and how do they differ from each other? Let's start our little "illiteracy" and figure out what the disc is and what it can be. We will recall the CDs from the nineties (CD), and from the two thousand (DVD), and many others.

Compact discs (CD)

CDs were invented by Philips back in 1979. The volume of the CD was such as to hold exactly 74 minutes of sound. Reading and writing information on the CD-ROM is done with the help of a directed optical laser beam. CDs have long been irrelevant in the world of computers. Now they are used only by record companies, since the volume of the media is quite enough to record quality sound.

But at one time CDs were quite popular among computer users. Earlier, when Windows distributions weighed slightly more than 600 MB, the CDs were widely used. But with the advent of "Seven", DVD-disks became actual. They are divided into several categories: CD-R (read only) - with the possibility of one-time recording and CD-RW (readable / writeable) - with the ability to repeatedly write. Of course, CD-RW was always a better option.

DVD and BlueRay disks

CD-ROMs were replaced by DVD-disks with a volume of 4.7 GB. This was more serious. On such a medium of information it was possible to record a bunch of movies in avi format. Yes, and the new-fashioned OS Windows 7 easily placed on them. DVDs are actively used in the film industry for the sale of films.

With the advent of BlueRay-discs, a new stage in the development of audio-video media began. With the huge volume of BlueRay it became possible to record movies as Full HD. What is a normal CD drive compared to BlueRay? A grain of sand in the sea. But this is not the end.

The final chord was the release of a two-layer "bluraya". That's really a monster among the "bastards". Information on it is placed twice as much as on the standard BlueRay, thanks to the ability to record immediately on two layers.

Hard disk (hard drive, HDD)

There are also devices that are used in computers to store data. They are called hard disks (HDD). So what is a HDD?

HDD (Hard Disk Drive) was first invented in 1973. And its memory was only 16 KB. At that time these were huge numbers. It consisted of 30 magnetic tracks and 30 cylinders. It is because of these figures that he was nicknamed the "hard drive". The hard disk consists of several plates on one vertical axis and a reading head with its own drive. Modern HDD can accommodate 2 TB of information. And this is not the limit.

HDD for laptops are slightly different from those "hard drives" that are usually installed in a PC. The hard drive for a laptop is much smaller than its "big brother". It goes without saying that with this size, the maximum amount of memory suffers. If the "full-size" HDD can accommodate 5 TB of information, and more, then the lath for HDD notebooks is much lower. A maximum of 2 TB.

Sometimes there are situations in which you have to change the HDD. Not that purchase will breach the budget, but it will not cost a penny to replace it. How much does an HDD drive you need volume, it is better to find out in specialized stores, not relying on the Internet. For BlueRay carriers, the average price is about 100 rubles, for DVD-RW - 30-35 rubles, and CDs are sold usually at a price not exceeding 20 rubles.

external HDs

There is still such a thing as an external hard drive. This is a comparable in size with HDD media, used where there is little capacity of the internal HDD. Usually, such drives are used for laptops, because to increase the amount of hard disk in them is quite problematic.

External HDDs are connected to the laptop via USB-input and have a maximum capacity of 2 TB. A pretty good plus for the laptop user. External hard drives come in different sizes: 2.5 and 3.5 inches. If the maximum disk capacity is 250-500 GB, then the volume of a 3.5-inch HDD can reach 2 TB. Naturally, 3.5-inch HDD in size and weight exceeds their "smaller brothers" and usually require a connection to the 220 V. If you need mobility, you will have to sacrifice volume.

An important factor when choosing an external drive is the USB 3.0 interface. Due to its presence, the write-read speed will be much higher than with the standard USB 2.0. In addition, it is worth paying attention to the presence in the HDD housing of its own cooler. Devices with a high number of revolutions per minute are quite noticeably heated, and to avoid overheating, it is useful to have a cooler.

As a rule, an external hard drive is much more expensive than a conventional HDD of the same volume, since it uses a completely different technology. But if you really need more space, it makes sense to spend it.

Startup disk

A startup disk is used for many tasks. But basically such a disk is called a storage medium, from which it is possible to install an operating system for a computer. For example, Windows, Linux or MacOS.

You can create a bootable disk even from a standard USB drive. With UltraISO, you can create a bootable USB or DVD-ROM drive. Bootable disks can be used not only to install the system. With their help, you can make a disk to scan systems for viruses before the OS boots.

Disc Reanimator

There is another subspecies of carriers - Reanimator. What is a Reanimator disk? This is the boot disk for system recovery. It includes programs for working with a hard disk, RAM and other hardware of the computer. If you have one, then perhaps you can do without reinstalling the entire system.

Reanimators were in great progress during the era of Windows 2000 and Windows XP. Now they are not so popular for the simple reason that new systems have their own recovery capabilities. However, in some cases, without the "Reanimator" simply can not do.

"Resanimators" could "pick up" a completely killed system. But it took a lot of time for this. Especially if "Resanator" was recorded on a regular CD. The speed of work was just turtle. With the ability to create a bootable USB-media, the situation began to be corrected. Now, "Resanator" takes much less time to "repair" the system. Even in our time, you need to have in your piggy bank drive "Resanator." Whether it is not enough that. It is not always possible to put the system "from scratch". Sometimes you can just restore it.

Conclusion

So, in this article, we looked at what a disk is, and what it can be. We reviewed CDs, DVDs, BlueRays, hard drives for PCs and laptops, external hard drives and boot options. Of course, all of them are said in general terms. To describe all the nuances and types of discs, one article is not enough. But in general, this information should help to understand which of them is intended for.