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Internet and Viruses

Internet and Viruses

A virus is a program that makes the computer slow and causes trouble.

  • Without the user’s knowledge, the program gets replicated itself by making multiple copies.
  • Viruses can be shared across globally which can affect numerous systems when connected to the internet.
  • There are chances where your computer can be hacked.

Why are they called Virus?

  • Computer viruses are called viruses, as they share some of the traits similar to biological viruses.
  • Like a biological virus passes from person to person, even computer virus passes from computer to computer.
  • Virus-infected computers can infect other programs or documents.


  class 7 internet and viruses


How will we know if our computer is virus affected?

  • Your system will be slow.
  • It will take time to load programs on your computer.
  • The documents stored in the system get corrupted or deleted.
  • The files get renamed with different names with some extension.
  • There will be frequent unusual error messages on the screen.

What are the ways can computer virus spread?

  • By opening an infected email link or an attachment from an unknown source.
  • By downloading infected programs from the internet.
  • It can also be transmitted through external storage such as an infected floppy disk, pen drives and CDs.

Type of computer virus

  • Spyware once installed to a computer, collects information about users without their knowledge.

  class 7 internet and viruses


  • Worm virus cannot get added to other program but it makes copies over and over and uses memory.


  class 7 internet and viruses


  • A trojan horse always does something destructive and are not self-replicating.

  class 7 internet and viruses



Classifications of Virus

A virus can be broadly classified into three categories:


class 7 internet and viruses


    Anti-Virus Software

Definition –

  • We can prevent our computer from virus attack with the help of Anti-virus software.
  • These are programs designed to prevent, detect and remove software viruses. 

Functions –

  • It helps to scan files or directories
  • It allows to schedule scans and it automatically runs to detect the virus
  • It allows to initiate a scan of a specific file of your computer, or of a CD or flash drive at any time
  • Removes any malicious code on detection


Ways to avoid the virus attacks –

  • Scan all the email attachment before opening them
  • Install your computer with a good anti-virus program to scan for viruses
  • Scan the disk frequently for viruses
  • Never install any pirated software


  class 7 internet and viruses


Below listed are the important tips on preventing malware safe from infecting your computer.

  • Install your system with anti-virus/malware software.
  • The installed anti-virus software to be kept up to date.
  • Schedule regular scans or automatic update of anti-virus software.
  • Secure your network; do not connect with unknown sources.
  • Before opening a link, check for the send and the content.
  • Keep your Information safe.
  • Avoid using free Wi-Fi or connecting to unknown sources.
  • All the files are to be backed up to date.
  • Use a strong password with a combination of alphanumeric.

Cyber Crime –

  • Cybercrime encompasses any criminal act dealing with computers and networks (called hacking).
  • Additionally, cybercrime also includes traditional crimes conducted through the Internet.
  • For example; Internet fraud, identity theft, and credit card account misuse or usage of a stolen card are considered to be cybercrimes.
  • These are illegal activities which are committed through the use of a computer and the Internet.

Backup and Restore –

To back and restore data was introduced by Microsoft Windows in Windows Vista OS and later versions allowed users to create backups and restore from backups.

To back up your files

  1. Open Backup and Restore by clicking the below

Start button >> Control Panel >> System and Maintenance >> Backup and Restore.

  1. Do one of the following:
  • If you've never used Windows first we have to backup, click Set up backup, and then follow the steps in the wizard.
  • If you've created a backup before, you can wait for your regularly scheduled backup to occur, or you can manually create a new backup by clicking Back up now.

Restore files from a backup

  1. Open Backup and Restore by clicking the below

Start button >> Control Panel >> System and Maintenance >> Backup and Restore.

  1. Do one of the following:
  • To restore your files, click Restore my files.
  • To restore the files of all users, click Restore all users' files. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.


A virus is a program that makes the computer slow and causes trouble.

  • How will we know if our computer is virus affected?
  • What are the ways can computer virus spread?
  • Type of computer virus - Spyware, Worm, Trojan horse
  • Classifications of Virus - Boot Virus, Program Virus, Macro Virus

Anti-Virus Software

Ways to avoid the virus attacks

Important tips on preventing malware

Cyber Crime

Backup and Restore

Quiz for Internet and Viruses


What term is used if a search engine returns a web page if a match is found?

a) Link
b) Hit
c) Blog
d) Success


Which of the following is not a feature of the Internet?

a) News Group
b) Designing
c) E-Mail
d) Chat


Before downloading which package can be downloaded through internet for testing purpose?

a) Shareware
b) Pirated Software
c) Backup Copy
d) Beta Software


Which of the following is a set of protocols?










In a network, if a computer shares resources to be used by others then that computer is called as?

a) Client
b) Mainframe
c) Server
d) Peer


Which one of the following is true with respect to URL?

a) An address of page on World Wide Web
b) A Computer Software Program
c) An Acronym For Unlimited Resource For Learning
d) A type of Programming Object


When computers are connected in LAN, then?

a) Computers do not interact
b) Computers can run faster
c) Computers can go on line
d) Computers can share information and can share peripheral equipment


Based on the packet's address, the device that has been designed to forward packets to specific ports is?

a) Speciality Hub
b) Filtering Hub
c) Switching Hub
d) Port Hub


_______ topology is not of a broadcast type?

a) Bus
b) Ring
c) Mesh
d) Star


Which one of the devices is needed to communicate with computers using telephone lines?

a) Modem
b) Disk
c) USB
d) VDU

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