System Software
System software consists of the programs, including the operating system,
that control the operations of the computer. The three major categories are:
operating systems, utilities, and language translators.
Operating Systems
An operating system (OS) is a set of programs that manages the operations
of a computer and functions as an interface among the user, the application
programs, and the computer hardware. The user interface determines how
users interact with the computer. A graphical user interface (GUI) uses
visual clues to help perform tasks. An operating system performs four
functions: process management, memory management, input and output management,
and system administration.
Process Management
In operating system terms, a process is a program or part of a program that
can be executed (run) separately. Single tasking operating systems allow only
one user to run one program at a time. Multitasking operating systems allow
the computer to work on more than one process at a time.
Memory Management
The operating system assigns the operating system kernel, application program
instructions, data, and intermediate results to areas of memory. Data that
has just been read into memory or is waiting to be sent to an output device
is stored in areas called buffers. At least some portion of memory is
allocated for fixed areas called partitions, which are used to store the
operating system and programs and their related data. Virtual memory
management increases the amount of memory by using a set amount of
disk space to store items during processing, in addition to the existing
memory.
Input and Output Management
The operating system manages input and output processes differently depending
on the device. Spooling increases both CPU and printer efficiency. The
operating system uses programs called device drivers to communicate with
each input and output device. With Plug and Play technology, the operating
system recognizes any new devices and assists in their installation.
System Administration
The operating system monitors system performance and system security.
System performance usually is gauged by the user in terms of response
time, which is the amount of time from when data is entered until the
system responds. To ensure system security, most multiuser operating
systems allow each user to have a logon code, a user ID, and a password.
All operating systems contain programs that perform functions related
to disk and file management. These functions include formatting disks,
listing files, deleting files, copying files, renaming files, and
organizing files.
Loading an Operating System
Loading an operating system is called booting. With the Windows 95
operating system, when the computer is turned on the CPU looks to the
BIOS (Basic Input/Output System) chip for instructions. The BIOS chip
tests the system and then looks for the boot program. The boot program
is loaded into memory and begins loading the resident portion of the
operating system. The operating system then loads system configuration
information. A device driver is loaded for each hardware device. The
remainder of the operating system is loaded and the desktop and icons
display on the screen.
Portable Operating Systems
The trend is toward portable operating systems that will run on many
manufacturers’ computers. Users can change computer models or vendors,
yet retain existing software and data files.
DOS and Windows 3.X
DOS (Disk Operating System) refers to several single tasking operating
systems that were developed for IBM-compatible personal computers.
Windows 3.x refers to versions of Microsoft’s Windows operating system.
Windows 95, Windows CE, and Windows NT
Windows 95 is a 32-bit operating system. It has an improved graphical
user interface, is written to take advantage of newer 32-bit processors
, and supports preemptive multitasking. Windows CE is an operating system
designed for use on wireless communications devices and smaller computers.
Windows NT is a sophisticated operating system designed for client-server
networks.
Macintosh, OS/2, UNIX, and Netware
The Apple Macintosh multitasking operating system was the first commercially
successful graphical user interface. OS/2 is IBM’s graphical user interface
operating system designed to work with 32-bit microprocessors. UNIX is a
multiuser, multitasking operating system available for most computers of
all sizes. NetWare from Novell is a widely used network operating system
designed for client-server networks.
Utilities
Utility programs perform specific tasks related to managing computer
resources or files. Utility programs include file viewers, file
conversion software, file compression software, backup software,
diagnostic programs, uninstallers, antivirus programs, screen savers,
desktop enhancers, and Internet organizers.
Language Translators
Special-purpose system software programs called language translators
convert the programming instructions written by programmers into binary
code that a computer can understand.
--
"Merciful and Helpful Goddess Office"
Sorry for the late introduction,but my name is "Belldandy".
I wish a goddess like you could stay with me forever !
--
※ 發信站: 批踢踢實業坊(ptt.twbbs.org)
◆ From: chintei.m1.ntu.
> -------------------------------------------------------------------------- <
作者: chintei (微積分是我的全部) 看板: NTUMEB87-C
標題: Re: 計概網站 ch.8 review
時間: Wed Jan 6 20:31:54 1999
※ 引述《chintei (微積分是我的全部)》之銘言：
: System Software
: System software consists of the programs, including the operating system,
: that control the operations of the computer. The three major
: categories(分類) are:
: operating systems, utilities, and language translators.
:
Starting up the computer,loading,executing(執行),storing
application programs(應用程式);storing & retrieving(讀取) flies ....
--
當人類經由訓練到了極限
剩下的力量就決定於 個人意志力的強弱 了
--
※ 發信站: 批踢踢實業坊(ptt.twbbs.org)
◆ From: chintei.m1.ntu.