Chapter 5

System Software

- It consists of the programs that control or maintain the operations of the computer and its devices

- Eg: Operating system (OS), utility programs

Operating System (OS)

- It is a set of programs containing instructions that work together to coordinate all the activities among computer hardware resources

- Activities such as:

Start and shut down a computer

Provide a user interface

Manage programs

Manage memory

Coordinate tasks

Configure devices

Establish an internet connection

Monitor performance

Provide utilities

Automatically update

Control a network

Administer security

OS Functions

- Booting is the process of starting or restarting a computer

- 2 types of booting:

Cold boot - Turning on a computer that has been powered off completely

Warm boot - Using the operating system to restart a computer

- A boot device is the drive from which your computer starts.

- A computer can start from a boot disk

- Boot disk is a removable digital data storage medium (CD-ROMs, USB flash drives, hard disks ) from which a computer can load and run an OS or utility program

- A recovery disc contains a few system files that will start the computer

- Recovery disc contains a backup of the original factory condition a computer as configured by an original equipment manufacturer (OEM)

- Recovery disk can also be created by an end-user which contains a favored condition of a computer

- An OS includes various shut down options:

Sleep - This mode saves any open documents and programs to RAM, turns off all unneeded functions and then places the computer in a low-power state

Hibernate - This mode saves any open documents and programs to a hard disk before removing power from the computer

- User interface controls how you enter data and instructions and how information is displayed on the screen

- With graphical user interface (GUI), a user interacts with menus and visual images

- With command-line interface, a user uses the keyboard to enter data and instructions

- Ways an OS handles programs directly affects its productivity: 

Single use and multiuser

Single tasking and multitasking

Foreground and background

Preemptive multitasking - It works on a time sharing feature, where each process may be allocated equal shares of computing resources

Multiprocessing

- Memory management optimizes the use of RAM

- Virtual memory is a portion of a storage medium functioning as additional RAM

- OS determines the order in which task are processed

- Driver is a small program that tells the OS how to communicate with a specific device

- Plug & Play automatically configures new devices as you install them

- OS typically provide a means to establish internet connections

- Performance monitor is a program that assesses and reports information about various computer resources and devices

- OS often provide users with the capability of:

Manage files

Search for files

View images

Secure a computer

Uninstall programs

Clean up disks

Defragment disks

Diagnose problems

Backup files and disks

Setting up screen savers

- Automatic update automatically provides updates to the program

- Some OS are designed to work with server on a network

- Server OS organizes and coordinates how multiple users access and share resources on a network

- A network administrator uses the server operating system to:

Add and remove users, computers and other devices

Install software and administer network security

- Each user has a user account

User ID identifies a specific user

Password is a private combination of characters associated with the user name

Store

Cortana

Microsoft Edge

- Macintosh OS has set the standard for OS ease of use

- Mac OS X is the latest version

- UNIX is a multitasking OS developed in the early 1970s

- Linux is an open-source, popular, multitasking UNIX-type OS

Server OS

Windows Server 2008

Linux

Solaris

Netware

- Windows Server 2008 is an upgrade to Windows Server 2003. Has multiple editions. Most editions include Hyper-V, a virtualization technology

- Virtualization is the practice of sharing or pooling computing resources

Embedded OS

- It resides on a ROM chip on a mobile device or consumer electronic device

- Eg: Windows Embedded CE, Windows Phone, Palm OS, iOS, BlackBerry OS, Android, Embedded Linux, Symbian OS

Utility Programs

- It is a type of system software that allows a user to perform maintenance-type tasks

- File manager is a utility that performs functions related to file management. It:

Display a list of files

Organise files in folders

Copy, rename, delete, move and sort files & folders

Create shortcuts

- Search utility is a program that attempts to locate a file on your computer based on criteria user specify

- Image viewer allows users to display, copy & print the contents of a graphics file

- Uninstaller removes a program, as well as any associated entries in the system files

- Disk cleanup utility searches for and removes unnecessary files, such as:

Downloaded program files

Temporary internet files

deleted files

Unused program files

- Disk defragmenter reorganizes the files and unused space an a computer's hard disk so that the OS accesses data more quickly and programs run faster

- Backup utility allows users to copy files to another storage medium

- Restore utility reverses the process and returns backed up files to their original form

- Screen saver causes a display device's screen to show a moving image or blank screen if no activity occurs for a specified time

- Personal firewall detects and protects a personal computer from unauthorized intrusions

- Virus describes a potentially damaging computer program that affects a computer negatively

- Worm copies itself repeatedly in memory or over a network

- Torjan horse hides within or looks like a legitimate program

- Antivirus program protects a computer against viruses

Chapter 4

• Differentiate among various styles of system units on desktop computers, notebook computers, and mobile devices
• Identify chips, adapter cards, and other components of a motherboard
• Describe the control unit and arithmetic logic unit components of a processor, and explain the four steps in a machine cycle
• Identify characteristics of various personal computer processors on the market today, and describe the ways processors are cooled
• Define a bit and describe how a series of bits represents data
• Explain how program instructions transfer in and out of memory
• Differentiate among the various types of memory
• Describe the purpose and types of expansion slots and adapter cards, and differentiate among slots for various removable flash memory devices
• Differentiate between a port and a connector, and explain the differences among a USB port, FireWire port, Bluetooth port, SCSI port, eSATA port, IrDA port, serial port, and MIDI port
• Describe the types of buses in a computer
• Explain the purpose of a power supply and describe how it keeps cool
• Understand how to clean a system unit on a computer or mobile device

What is a System Unit ? 

• The system unit is a case that contains electronic components of the computer used to process data
• The inside of the system unit on a desktop personal computer includes Drive Bay(s), Power Supply, Sound Card, Video Card, Processor, Memory.
• The main circuit board of the system unit is Motherboard
• A computer chip contains integrated circuits

What is Processor ?

• The processor, also called the central processing unit (CPU), interprets and carries out the basic instructions that operate a computer
• Contain a control unit and an arithmetic logic unit (ALU)
• The control unit is the component of the processor that directs and coordinates most of the operations in the computer
• The arithmetic logic unit (ALU) performs arithmetic, comparison, and other operations

What is Memory?

• Memory consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data
• Stores three basic categories of items. Example [The operating system and other system software, Application programs, Data being processed and the resulting information]
• Each location in memory has an address
• Memory size is measured in kilobytes (KB or K), megabytes (MB), gigabytes (GB), or terabytes (TB)
• The system unit contains two types of memory which are Volatile memory and Nonvolatile memory

1. Volatile memory - Loses its contents when power is turned off. Example includes RAM
2. Nonvolatile memory - Does not lose contents when power is removed. Examples include ROM, flash memory, and CMOS

There are some type of basic types of RAM chips exist

Dynamic RAM (DRAM)

Static RAM (SRAM)

Magnetoresistive RAM (MRAM)

1/9/16

juz finish chapter 2 today
i learn internert what i use many year but dont know what is it@@
these are what i learn in chapter 2:
i)identify a URL
ii)describe the types of Web pages
iii)recognize Web pages
iv)explain how e-mail,FTP,chat room,chat and instant messaging work
v)coming soon~

ms wan suddenly tell us today is her birthday,then we sing the happy birthday song to ms immediately,its fun and happy today✧٩(ˊωˋ*)و✧

30/8/16

its raining today,so i miss the class after i trying to go school( ºΔº )〣

29/9/16

today is the first day for this semester,its oso the first day i learn the CA,i feel its a fun course.I will do my best in this course╮(‵▽′)╭