Information Technology Reference
In-Depth Information
File Management
The OS manages files to ensure that files in secondary storage are available when needed and
that they are protected from access by unauthorized users. Many computers support multiple
users who store files on centrally located disks or tape drives. The OS keeps track of where
each file is stored and who can access it. The OS must determine what to do if more than
one user requests access to the same file at the same time. Even on stand-alone personal
computers with only one user, file management is needed to track where files are located,
what size they are, when they were created, and who created them.
Current Operating Systems
Early OSs were very basic. Recently, however, more advanced OSs have been developed,
incorporating sophisticated features and impressive graphics effects. Table 4.2 classifies a few
current OSs by sphere of influence.
Table 4.2
Personal
Workgroup
Enterprise
Popular Operating Systems
Cross All Three Spheres of
Influence
Microsoft Windows Vista,
Windows XP, Windows
Mobile, Windows Automotive,
and Windows Embedded
Microsoft Windows Server
2003 and Server 2008
Microsoft Windows Server
2003 and Server 2008
Mac OS X
Mac OS X Server
UNIX
UNIX
UNIX
Solaris
Solaris
Solaris
Linux
Linux
Linux
Red Hat Linux
Red Hat Linux
Red Hat Linux
Palm OS
Netware
IBM i5/OS and z/OS
IBM i5/OS and z/OS
HP-UX 11i
HP-UX 11i
Microsoft PC Operating Systems
Since a small company called Microsoft developed PC-DOS and MS-DOS to support the
IBM personal computer introduced in the 1980s, personal computer OSs have steadily
evolved.
PC-DOS
and
MS-DOS
had command-driven interfaces that were difficult to learn
and use. Each new version of OS has improved the ease of use, processing capability, relia-
bility, and ability to support new computer hardware devices.
Windows XP
(XP reportedly stands for the positive experience that you will have with
your personal computer) was released in fall 2001. Previous consumer versions of Windows
were notably unstable and crashed frequently, requiring frustrating and time-consuming
reboots. With XP, Microsoft sought to bring reliability to the consumer.
In 2007, Microsoft released Windows Vista to the public, introducing it as the most
secure version of Windows ever. Windows Vista includes design improvements that make it
attractive and easy to use. The most advanced editions of Windows Vista include a 3-D
graphics interface called Aero. However, the system requirements for Windows Vista with
Aero require many users to purchase new, more powerful PCs. Windows Vista also suffered
some negative press when early adopters found that some software and hardware designed
for Windows XP did not run on Vista.
Windows Vista is available in five editions. Windows Vista Home Basic provides im-
proved security, but otherwise has features similar to those included in Windows XP.
Windows Vista Home Premium includes enhanced security, the Aero interface, and other
improvements such as home media, but lacks business features. Windows Vista Business
includes all of the above except the home media features plus business features such as a
backup and restore tool, a scan and fax tool, and easy access to business networks from home.
