Types of file systems

The file system organizes files so that the operating system can more easily work with them: the file system drivers transmit the OS information about thethe names of the files, their size, attributes, locations. The file system determines the maximum possible length of the file name, its maximum size and other parameters.

For different media, there are different types of file systems. By the way, the medium does not need to be physical: there are, for example, virtual and network file systems. What are the types of file systems depending on their purpose, that is, the medium?

First of all, the user is faced with file systems designed for media with random access. Such carriers include, for example, hard disks. If you use the Windows operating system, then most likely you are dealing with a file system NTFS. Older versions of the operating system used a file system FAT32, which is still used on flash drives.

In many operating system distributions based on the Linux kernel, the default file system is usually used ext (Extended File System - extended file system). There are several versions of this file system - ext2, ext3, ext4. In the latest versions of distributions based on the Linux kernel (including Google Android), the file system is ext4.

Its file systems are optical media - CD and DVD discs. A standard is considered standard ISO 9660, such disks are read by computers with any operating system - Windows, Mac OS X, Unix. There is also a file system format UDF, which is more suitable for large discs (DVD, Blu-ray). There are other file systems for optical disks, less common.

With hard disks, flash drives and optical disks, we encounter more often than with other carriers, so their file systems are of interest to us the most. But still it is worthwhile to know what other types of file systems there are:

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  virtual file systems;
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  network file systems;
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  file systems for sequential access media (they include, say, magnetic tapes);
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  file systems for flash memory;
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  specialized file systems.

Let's talk a little more about the types of file systems designed for media with random access, for example, hard drives and flash drives. The type of a particular file system affects the file settings, for example, the size of the file name. In the FAT32 system, the maximum length of the file name- 255 characters. In NTFS, according to the specification, there are 32,768 characters, but some OSs impose a limitation, so in reality the maximum length will be all the same 255 Unicode characters. In ext2 / ext3, the name length is limited to 255 bytes.

Also from the file system depend on the possible attributes of the file. For example, FAT32 and NTFS systems allow you to assignfiles the attributes "read-only", "system", "hidden", "archive". And the ext2 system offers attributes such as "setting a user ID", "setting a group ID" and the so-called "sticky bit".

There are also differences between the FAT32 and NTFS file systems. Both of these file systems are used by the OSWindows, the NTFS system replaced FAT32 and is used in the latest versions of the OS. In the FAT32 system, the disk size is limited to about 8 terabytes, in NTFS it can be 264 bytes. The maximum file size in FAT32 is 4 GB, in NTFS it is 264 bytes minus 1 kilobyte (theoretically), and in fact - 244 bytes minus 64 kilobytes. Also NTFS has more maximum number of files, there are some other differences.

But in this case The FAT32 system is still used on USB flash drives (flash drives), because it provides a higher speedrecording, reading and copying data. Therefore, most flash drives are formatted in FAT32, not NTFS. Formatting a USB flash drive in NTFS makes sense only if you need to write a file larger than 4 GB on it.

Now you know, what are the main types of file systems and in which cases you may encounter a particular file system.