Monday 26 August 2013

Computer System


What is a computer system?????

a system of one or more computers and associated software with common storage.

Latest desktop with latest operating system (Windows 8)



List of computer system:

Input
• Any data and instruction entered into memory of 
computer
Output
• Data that has been processed into a useful form.
Process
• Transform an input data flow into an output data 
flow.
Storage
• Hold data instructions and information for future
use.
Information processing cycle6
 Information processing cycle is the series of 
input, process, output and storage 
activities.
 Computer process data (input) into 
information (output)
 Computer holds data, information and 
instructions in storage for future use 
Information processing

Component of computer(Hardware)

A computer contains many electric, electronic, and 
mechanical components known as hardware.
-Input Device - Allows you to enter data and instructions into a computer
-Output Device - Hardware component that conveys information to one or more people
-System Unit - Case that contains the electronic components of the computer that are used to process data             
-Storage Device - Records (writes) and/or retrieves (reads) items to and from storage media 
-Communication Devices - Enables a computer to send and receive data, instructions, and information to and from one or more computers or mobile devices

Examples of Input Devices


Examples of Output Devices





Motherboard

a printed circuit board containing the principal components of a computer or other device, with connectors into which other circuit boards can be slotted.






Every motherboard has connectors and slots to connect all the remaining parts of CPU. here the list of all the slot and connector of motherboard.
  • CPU Socket
  • North Bridge
  • South Bridge
  • RAM Slots
  • AGP Slot
  • PCI Slots
  • CNR Slot
  • Floppy Connector
  • Primary and Secondary IDE Connectors
  • SATA connectors
  • Power Connector
  • BIOS
  • CMOS battery
  • Ports
CPU Socket:

CPU Socket or Processor Socket. Which is used to install or insert the processor. we have two types of sockets. LIF sockets and ZIF socket. LIF stands for Low Insertion Force, this is the old model sockets and ZIF stands for Zero Insertion Force, this is the present model sockets. 


 
LIF socket or slot type processor socket
ZIF socket or PGA sockets
North Bridge:

North Bridge is always near the processor socket. which is one of the important component of a motherboard. It is a focal Point of Motherboard and It is also called as Memory Controller Hub. North Bridge interconnects Processor socket, RAM slots and AGP slot. here Gigabyte chip is north bridge it is near Processor socket.


South Bridge:

North bridge and south bridge are the two main poles of a motherboard. South Bridge interconnects Primary and Secondary IDE interfaces, SATA connectors, Floppy Drive Connector, PCI slots and BIOS. 


RAM Slots

RAM slots are used to insert RAMs. there are so many types of ram slots. they are SD ram slots, DDR ram slots, DDR2 and DDR3 ram slots. SD stands for synchronize Dynamic and DDR Stands for Double Data Rate.


AGP slot:

AGP slots are used to insert or install AGP Cards. AGP full form is Accelerated Graphics Port. This slot is for graphics and 3d gaming purpose. it is always beside the PCI slots


PCI slots:

PCI slots are used to Insert or install Add-on cards, such as LAN cards, Sound cards, Capture cards and TV tuner cards. PCI full form is Peripheral Component Interconnect.


Floppy Drive Connector:

Floppy Drive Connector is used to connect floppy drives. It supports two floppy drives. so that A and B drives are reserved for two floppy drives in My computer. it has 32 pins. 

Primary and Secondary IDE Interfaces:

Primary and Secondary IDE interfaces are also called as IDE connectors or PATA connectors. IDE full form is Integrated Device Electronics. it supports IDE devices, such as Hard disks and CD and DVD drives.


SATA Connectors:

SATA connectors are also called as Serial ATA connectors. SATA full form is Serial Advanced Technology Attachment. These are connect with serial ATA devices, such as Hard disk drives and CD or DVD drives.


Power Connector:

This power connector is ATX power connector. it has 20 or 24 pin connector. mother takes the power from this connector to work.

BIOS:

BIOS stands for Basic input and Output system. This is also one of the important chips. it conducts the POST (Power On Self Test).


CMOS battery:

There is a battery in the motherboard, which is used to power the south bridge and the BIOS to save the setting, data and time.

 Ports:

Ports are used to connect input and output devices. they are attached and come with motherboard and they are in backside of CPU.

Memory

Internal storage areas in the computer. The term memory identifies datastorage that comes in the form of chips, and the word storage is used for memory that exists on tapes or disks. Moreover, the term memory is usually used as a shorthand for physical memory, which refers to the actual chips capable of holding data. Some computers also use virtual memory, which expands physical memory onto a hard disk.
Every computer comes with a certain amount of physical memory, usually referred to as main memory or RAM. You can think of main memory as anarray of boxes, each of which can hold a single byte of information. A computer that has 1 megabyte of memory, therefore, can hold about 1 million bytes (orcharacters) of information.
There are several different types of memory:



  • RAM (random-access memory): This is the same as main memory. When used by itself, the term RAM refers to read and writememory; that is, you can both write data into RAM and read data from RAM. This is in contrast to ROM, which permits you only to read data. Most RAM is volatile, which means that it requires a steady flow of electricity to maintain its contents. As soon as the power is turned off, whatever data was in RAM is lost.
  • ROM (read-only memory): Computers almost always contain a small amount of read-only memory that holds instructions for starting up the computer. Unlike RAM, ROM cannot be written to.
  • PROM (programmable read-only memory): A PROM is a memory chip on which you can store a program. But once the PROM has been used, you cannot wipe it clean and use it to store something else. Like ROMs, PROMs are non-volatile.
  • EPROM (erasable programmable read-only memory): An EPROM is a special type of PROM that can be erased by exposing it to ultraviolet light.
  • EEPROM (electrically erasable programmable read-only memory):An EEPROM is a special type of PROM that can be erased by exposing it to an electrical charge.



  • Storage

    Computer data storage, often called storage or memory, is a technology consisting of computer components and recording mediaused to retain digital data. It is a core function and fundamental component of computers. The central processing unit (CPU) of a computer is what manipulates data by performing computations. In practice, almost all computers use a storage hierarchy, which puts fast but expensive and small storage options close to the CPU and slower but larger and cheaper options farther away. Often the fast, volatile technologies (which lose data when powered off) are referred to as "memory", while slower permanent technologies are referred to as "storage", but these terms can also be used interchangeably. In the Von Neumann architecture, the CPU consists of two main parts:control unit and arithmetic logic unit (ALU). The former controls the flow of data between the CPU and memory; the latter performs arithmetic and logical operations on data.



    Application software

    Application software, also known as an application, is computer software designed to help the user to perform singular or multiple related specific tasks. Examples include enterprise software, accounting software, office suites, graphics software, and media players.



    Type of software:
    -Open source software
    -Packaged software
    -Shareware
    -Freeware
    -Webapplication
    -Public-domain software
    -Custom software

    System software

    system software (or systems software) is computer software designed to operate and control the computer hardware and to provide a platform for running application software.[1][2]
    System software includes the following:
    In some publications, the term system software also includes software development tools (like a compilerlinker or debugger).[3]
    In contrast to system software, software that allows users to do things like create text documents, play games, listen to music, or surf the web is called application software.

    Example of operating system

    Example of utility program-a type of system software that allows user to perform maintenance-type tasks.