Information Technology Reference
In-Depth Information
Quick Review
1 Name the Windows version designed for each of these platforms: desktop computer, tablet, smartphone, and server.
2 Name three operating systems for smartphones.
Understanding Digital Storage
Most operating systems save and store files using the same basic prin-
ciples, although the individual file formats may differ between platforms
and operating systems. The following sections describe the logical orga-
nization of computer file systems.
Drives, Volumes, and File Systems
A drive is a physical storage unit, such as an HDD, a SSD, or a DVD
drive. As you learned in
Chapter 3, “Input, Output, and Storage,”
some
drives are separate from their discs, as a DVD drive is. Other drives have
the discs built-in, like in an HDD. And some drives are not technically
“drives” at all, in that they have no moving parts, but are called drives
for consistency; solid-state drives are an example of that. The term
hard
drive
generically refers to both HDD and SSHD storage in popular
usage.
Each drive has one or more volumes, which are logical divisions of storage
areas. Volumes are represented by letters, such as C:. A small-capacity,
removable storage device like a DVD or a USB flash drive has a single vol-
ume letter. A large-capacity storage device like an HDD or SSHD may be
divided into multiple volumes.
To prepare a hard drive for use, it must first be partitioned.
Partitioning
creates the logical divisions of the available space. A physical drive can
logically be a single volume (one big partition with one volume letter
assigned), or it can be split up into many pieces, each with its own vol-
ume letter. Each volume must then be formatted.
Formatting
organizes
the available space by creating a
file system
on it. The file system deter-
mines how the files will be stored and retrieved logically.
partition
To create logical divisions of the
available space on a storage medium such as an
HDD; or, a logical division of space on a storage
medium.
format
To create the file system on a volume.
file system
A set of rules for storing and manag-
ing the files on a volume, such as NTFS or FAT32.
Depending on the operating system and the utility you are using to parti-
tion and format the drive, different file systems may be available. Table 4.1
lists several popular file systems. Modern versions of Windows prefer the
New Technology File System (NTFS)
for the
system volume
(that is,
the volume on which Windows itself is installed), but can also support
FAT32
, a file system used in earlier Windows versions. Mac OS X uses a
file system called
Hierarchical File System Plus (HFS+)
. Linux supports
several different file systems, and the default file system installed depends on
the distro. CDs and DVDs commonly use the
ISO 9660
(also called CD
File System, or CDFS) or the
Universal Disc Format (UDF)
file system.
New Technology File System (NTFS)
The
proprietary Microsoft file system used in modern
versions of Windows.
system volume
The volume on which the
operating system files are stored.
FAT32
A file system used in Windows 95,
Windows 98, and Windows Millennium Edition. FAT
stands for File Allocation Table.
Hierarchical File System Plus (HFS+)
The
file system used with Mac OS X.
ISO 9660
A file system used on optical media
such as CDs; also called CD File System, or CDFS.
Different file systems offer different features and benefits. NTFS, for
example, provides features like file encryption, file compression, support
for long filenames (up to 255 characters), and support for large-capacity
volumes (up to16 TB). You will learn about file encryption and compres-
sion later in this chapter.
Universal Disc Format (UDF)
An extension
of the ISO 9660 file system, a file system used on
optical media such as CDs and DVDs.
