Types Of Networks

1. Peer- to-Peer network

In this network no computer set-aside as a server but all computers operator as equals.Each computer is called peer.Each computer can acts as a client or server.Each computer is responsible for its own security.It is small networks having number of computers less than 10


The network is easy to operate.

The resorce sharing is simple.

It is cost effective for small network.


It is not useful for database application.

It cannot maintain security.

It cannot be used for large networks.

2. Server-Based network

In this network one computer is set-aside as a server and remaining all computer acts as client.The server processes all the request made by the client.server is high performance system.It has faster CPU and more disk space amd memory size.The server is operateb by network.Operating system


The network is more secure..

It is used in large network.

It is useful for database application..


It is difficult to install the network.

It is not cost effective as cost of server is large then the client.

Computer Viruses

                                          A computer virus is a computer program that can infect your computer system by executing itself without your permission or knowledge and run against your wishes. Viruses can also replicate itself to maximum the infection.   

                                         Viruses can infect the normal functioning of the computer in many ways. some viruses may display only a message on the screen whereas other may slow –down your pc or may cause extensive damage to your system  . for an instant, they may change computer files so that programs do not work properly or even stop working. They can also erase files or even format your hard disk and crash the system.

                                         viruses are also easily spread by carrying it on a removable medium such as floppy disk, USB drive or cd. Computer viruses are most easily spread by attachment in e-mail messages or by instant messaging or by instant messaging message.

The following are some primary indicators that a computer may be infected

1. The computer runs slower than usual.

2.the computer stops responding, or it.

4. The computer crashes, and then it restarts every few minutes.

5. The computer restarts on its own. Additionally, The computer does not run as usual.3.

6. Application on the computer does not work correctly.

7. Disks or disk drives are inaccessible.

8. You see unusual error messages.

9. An antivirus program is disabled for no reason. Additionally, the antivirus program cannot be restarted.

10. An antivirus program cannot be installed on the computer, or the antivirus program will nor run.

11. A program disappears from the computer even though you did not intentionally remove the program.


Antivirus Software:-Is a computer program that detects, prevents, and task action to disarm or remove malicious software program, such as viruses and worms .you can help protect your computer against viruses by using antivirus software, Such as Norton Antivirus, Avast antivirus, McFee, Kaspersky,e, Bitdefender Antivirus, F-Secure Antivirus

To protect a computer against Viruses follow these steps,

  • On the computer, turn on the firewall.
  • Keep the computer operating system up-to-date.
  • Use updated antivirus software on the computer.
  • Use updated antispyware software on the computer

Maintaining The Computer

                                    Microsoft has created a pair of built-in automated troubleshooting packs to optimize and maintain performance. window 7,8,8.1,10  window 7,8,10 handles lots of lots of files. So, you need to organize files in logical ways and perform maintenance activities from time to time. Windows provides three tools to help manage the files and folder stored on hard disks 

Disk cleanup help to get rid of old files on your hard disk. The window looks through your hard disk for types of files that can be deleted and list them. You can then select the type of files you want to delete.

Follow Step-By-Step

  1. Click on My computer.Then select on C: Drive.
  2. Right-click on c drive then select on properties.This will display the disk properties window on your screen. 

3. Click on disk cleanup button.windows will calculate how much space you could save.

Disk cleanup

4.Select the type of files to delete, and click ok

5. You are asked if you want to permanently delete these files. Click delete files to permanently delete them.

6. When you are ready, close the properties dialog box.

Basic of computer network


               Each of the past three technologies has been dominated by a single technology. The 18th century was the era of the great mechanical system, The 19th century was the age of the steam engine. During the 20th century, the key technology was information Gathering, Processing, And Distribution.

             As a result of rapid technological progress, these areas are rapidly converging and the differences between collecting transporting, storing and processing information are quickly disappearing.  


      • Human Network.
      • Computer Network.
      • Network Plan

2. Computer Network

  • Access to the world wide web (www).
  • Shared use of application & storage servers.
  • Shared use of Printer and fax machine.
  • Use of E-mail & instant messaging services.

3.Network Plan

         To connect the computers in the network in case of a large organization, may be confusing and also difficult to track various problems. 

        Hence we should have a plan for a computer network. The plan shows how all the networks component are devices are connected so that this is known as network plan

Network Feature

  • File sharing
  • Printer sharing
  • Application sharing
  • E-mail
  • Remote access
  • Internet and Internet
  • Network security

Advantages of computer network

  1. Increased speed
  2. Reduced cost
  3. Improved
  4. Flexible access
  5. Electronic software manegers

what is the os

what is the operating system

                  An Operating system is a program, which acts as an interface between a user of a computer and the computer hardware. So the Propose of an operating system is to provide an environment in which a user may execute programs. The primary goal of an operating system is thus to make the computer system. And convenient to use OS is the most important program that runs off the computer. The operating system performs basic tasks such as recognizing input from that run of a computer.

                An operating system performs basic tasks such as recognizing input from the keyboard, And sending the output of the monitor, Keeping track of files and directories on the disk and controlling peripheral devices such as disk drives and printers.

 Type of OS

                Below is a basic list of the different types of operating systems and a few examples of operating systems that fall into each of the categories. And many computer operating systems will fall into more than one of the below categories.

GUI Operating System

                 And the GUI operating system contains graphics and icons and is commonly navigated by using a computer mouse.

*Below are some examples of GUI operating system.*

  • Microsoft window
  • Mac OS
  • X window system

Multi-User Operating  system

                 A multi-user operating system allows, for multiple users to use the same computer at the same time and Or different times.

Below is some example of the multi-user operating system.

  • UNIX
  • VMS

Multiprocessing Operating System

              An operating system capable of supporting at utilizing more than one computer processor.

Below is the same example of a multiprocessing operating system.

  • UNIX
  • OS/2

Multitasking Operating system

              An operating system that is capable of allowing multiple software processes to run at the same time.

Below is the same example of the multitasking operating system.

  • Linux
  • Microsoft Window

Multithreading Operating System

              A multithreading operating system is an operating system that allows different parts of a single software program to run concurrently. Multithreading is the ability of an OS to execute different parts of the program.

The operating system that would fall into this category is.

  • Linux
  • UNIX
  • Window 2000


Components of a Computer

Components of a Computer

                   Because component of a computers are made up of two parts. The hardware and the software. And the physical equipment required to create, use, manipulate and store electronic data is referred to as hardware. So the computerized instructions that operate a computer manipulate. The data and execute particular functions or tasks are referred to as software.

All computers require the following hardware components.

Central Processing Unit (CPU).

                      This is also known as the brain of a computer. This is a single chip (sometimes more than one chip) located at the heart of a computer that enables it to process data. Also known as a processor. The part of the computer that executes the program is known as the processor or central processing unit. (CPU) The speed of a CPU chip is measured in GigaHertz(GHz).

Arithmetic Logic Unit

                     Arithmetic Logic Unit performs two types of operations. Arithmetic And Logical.Arithmetic operations include addition,subtraction,Multiplication,and division.

                   The logical operation consists of comparing one data item to another to determine if the first data item is greater than, equal to or less than the other.

Computer Memory

             This is an area within a computer system that holds data waiting to be processed.

           There are primarily two types of computer memory. One is the main or primary or internal memory. And the other is the secondary or auxiliary memory. Internal memory is the memory used by the computer’s processor to run its application, program and operating system.

      This Internal memory is often referred to as RAM, which stands for RANDOM ACCESS MEMORY

                   The other form of memory is the auxiliary memory which is where the computer will store information that is user-generated. Examples of auxiliary memory are your hard disk, your CD-ROM’s and DVDs.


                     Primary memory is the memory that communicates directly with the CPU. Primary memory is made up of silicon chips. Primary memory has the following two types.

  • RAM
  • ROM


                      When you want to keep data or information permanently, you need to transfer the data from primary memory to a magnetic disk or optical disk.

                 The main function of the secondary storage devices is storage and retrieval. There are three common types of secondary storage floppy disk, hard disk, and CD-ROM

  • Floppy Disks
  • Hard Disks
  • Optical Disks

Input Devices

                   An input device is any machine that feeds data into a computer. The devices that allow data and instructions to be entered in a computer.

  • Keyboard
  • Mouse
  • Track Ball
  • Joystick
  • Scanner

Output Devices

                         The output is anything that comes out of a computer. Output can be meaningful information and can appear in a variety of forms. The devices that allow information to be represented (i.e., given out ) to the user, such as a display screen or printer).

  • Monitor
  • Printer

Input-Processing-Output Cycle

Input-Processing-Output Cycle            This is the termed as input Processing output cycle .A computer receives data as input ,processes it, Stores it and then produces output. Input, Process, Output, and Conventional Technology To provide a better understanding of input, output, and processing, these concepts are defined as follows. Input – the information entered into a computer system, examples include typed text, mouse clicks, etc. Processing – the process of transforming input…

"Input-Processing-Output Cycle"

Benefits of computer

Benefits of a computer     Introduction  We are living in the age of computer.Most of our daily activities are being influenced by the use of computer.Computer you have become an integral part of our lives.   A computer is an automatic electronic machine that converts raw data into useful information with the help of certain intruction.These instruction are issued in form of aprogram. A programis a sequence of insructions,Written in a specific computer language,Which…

"Benefits of computer"