Sunday, February 13, 2011

CHAPTER 5 SYSTEM SOFTWARE


System Software
> Works with end users, application software, and computer hardware to handle the majority of technical details.
> consists of 4 types of programs :

Operating system -  coordinate computer resources, provide an Interface between users and the computer, and run programs.

Utilities - perform specific tasks related to managing computer resources.

Device Drivers - allow particular input or output devices to communicate with the rest of the computer system.

Language Translator - convert programming instructions written by programmers into a language that computers can understand and process.


OPERATING SYSTEM
> The nucleus of all software activity.
> The operating system is the most important program that runs on a computer. Every general-purpose computer must have an operating system to run other programs. Operating systems perform basic tasks, such as
  • recognizing input from the keyboard
  • sending output to the display screen
  • keeping track of files and directories on the disk
  • controlling peripheral devices such as disk drives and printers.

                                   Operating system graphic

[Operating System] [Image]. (n.d.). Retrieved from http://depts.alverno.edu/cil/mod1/software/system.html
> Function
  - Providing a graphical user interface (GUI) and running applications such as multitasking allows switching between different applications stored in memory. 
  - Managing computer's resources including memory, processing,storage, and devices. They also monitor system performance, schedule tasks, provide security and startup computer.


> Features
  -  Booting starts (cold boots) or restarts (warm boots) a computer system. The desktop provides access to computer resources. Common features include icons, pointers, windows, menus, dialog boxes, and Help. Data programs are stored in a system of files and folders.

> Categories
  - Embedded operating system are used for handheld devices such as smart Phone, PDA. The entire operating system is stored within or embedded in the devices includes ROM (read-only-memory) located on network server.
  - Network operating system are used to control and coordinate networked computer. It only connect a limited number of microcomputers.

> Stand-alone operating system usually called as desktop operating system, control a single desktop or laptop located on local hard disk.


Different Types of Operating System

Window
 - The most widely used operating system, is designed to run with Intel and Intel-compatible microprocessors. There are numerous versions of window. Window 7 is the most recent versions of Window. It provides improved handwriting recognition, taskbar with previews, large icons, and personalization features, and advanced search capabilities.

Mac OS
 - An innovative, powerful, easy to use operating system, runs on Macintosh computers. Recent versions provide Spotlight, an advanced search tool, and Dashboard Widgets, a collection of specialized programs. Some versions of MAC OS X come with Boot Camp, which allows Macintosh computers to run both MAC OS and Window OS.

UNIX and LINUX
 - Under UNIX, the Operating System consists of many programs along with the master control 
   program, the kernel.      
   The kernel provides services to start and stop programs, handles the file system, etc.
 - The original name was UNICS which stands for UNiplexed Information and Computing Services. 
 - UNICS was later renamed to UNIX (UNIX is not an acronym).
 - UNIX was attractive to other organizations and universities for a few reasons [3]:

  • It was the only powerful interactive system that could run on the sort of hardware that universities could afford in the mid ’70s.
  • It was written in an attractive language, C.
  • When UNIX got into the hands of many teachers and students and individuals around the world, it got further improved and became popular since.
EXAMPLE :


  The computer the first UNIX version was created in, model: DEC PDP-7
  Manufacturer: Digital Equipment Corporation
  Year: 1965
  Price: $72,000 USD
  Power: less than a typical cellphone of today

[UNIX] [Image]. (n.d.). Retrieved from 
http://www.unixnewbie.org/what-is-unix-and-linux/

Linux is a UNIX clone. It was created at the University of Helsinki in Finland by a student named Linus Torvalds in 1991.
The Linux operating system is developed under the GNU General Public License (also known as GNU GPL) and its source code is freely available to everyone.

Linus Torvalds

[LINUX] [Image]. (n.d.). Retrieved from 
http://www.unixnewbie.org/what-is-unix-and-linux/

Utilities
 - Utility software is a kind of system software designed to help analyze, configure, optimize and maintain the computer.
 - Utility software should be contrasted with application software, which allows users to do things like creating text documents, playing games, listening to music or surfing the web. Rather than providing these kinds of user-oriented or output-oriented functionality, utility software usually focuses on how the computer infrastructure (including the computer hardware, operating system, application software and data storage) operates.
 - The most essentials are troubleshooting, antivirus, uninstall, backup, restore, and file compressions.

Device Drivers
 - Allow communications between hardware devices. Add a Device Wizard gives step by step guidance to install printer devices drivers. Window update automates the process of updating the devices drivers versions.


*** Information is getting from the book - Computing Essential 2011