Computer & Main Parts of Computer – Security and Terminology of Computers

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Computer Security

Computer Security is the process of preventing and detecting unauthorized use of your computer.

Internet Security Threats

1. Virus is a type of malicious software program (malware) that, when executed, replicates by reproducing itself (copying its own source code) or infecting other computer programs by modifying them Ex: Code Red, Nimba, SirCam, Melisa, Ripper, MDMA, One _Half

  • Boot virus (Trojans) affect the disk operating system, thereby corrupting the booting files in spite of the operating system used. The main distinction is that they don՚t replicate but spread on opening an email attachment specifically.
  • Macro virus (Worms) are intended to affect data files specifically by finding vulnerabilities in word or excel documents. They infect by replicating to other systems in the network. They don՚t require a host file to replicate themselves.
  • Virus hoax is a message warning the recipients of a non-existent computer virus threat.
  • Companion virus is a complicated computer virus which, unlike traditional viruses, does not modify any files

2. Spyware: It is a software that secretly collects user information while on the internet. Spyware can capture information like web browsing habits, email messages, usernames and passwords, and credit card information.

3. Adware: This program launches the advertisements in the form of pop ups. Usually the add words are based on the internet behaviour of the user.

4. Spam: These are unwanted emails. In other words, we can call them as unsolicited promotional mail.

5. Pharming: More advance method of Phishing in which the attackers create duplicate or similar looking website of other companies, to attract the customers and steal the data.

6. Cookies: These are program or information secretly stored in a computer especially the internet browser, which allows other users to monitor the internet activities of a person. These programs usually monitor the browsing nature of person so that the companies can create better marketing strategies.

7. Mail Bomb: An excessively large email (typically many thousands of messages) or one large message sent to a user՚s email account. This is done to crash the system and prevent genuine messages from being received.

8. Scareware: A common trick cyber criminals use to make users think that their computer has become infected with malware to get them to purchase a fake application.

9. Sniffers: A software program used to monitor the traffic in a network. The hackers may use the sniffed data to access important confidential data. 10. Rootkit: A program designed to hide objects such as processes, files or Windows registry entries (often including its own) .

11. Phishing: This is acquiring the personal and sensitive information of a person through official looking emails. Users of online banking and e-commerce websites are more prone to this attack.

12. Spoofing : It is a type of scam where an intruder attempts to gain unauthorized access to a user՚s system or information by pretending to be the user.

  • Firewall is a network security system that monitors and controls the incoming and outgoing network traffic based on predetermined security rules.
  • Adware, or advertising-supported software, is any software package that automatically renders advertisements in order to generate revenue for its author.
  • Anti-virus software is a program or set of programs that are designed to prevent, search for, detect, and remove software viruses, and other malicious software like worms, trojans, adware.
  • zombie is a computer connected to the Internet that has been compromised by a hacker, computer virus or trojan horse program and can be used to perform malicious tasks of one sort or another under remote direction.

Computer Terminology

  • Access - To call up information out of storage.
  • Access time - The amount of time it takes for requested information to be delivered from disks and memory.
  • Accumulator A local storage area called a register, in which the result of an arithmetic or logic operation is formed It contains a single data register.
  • Adapter - A circuit board that plugs into a computer and gives it additional capabilities.
  • Amplifier -A device that takes in a weak electric signal and sends out a strong one.
  • Analog Computer - A computer that operates on data which is in the form of continuous variable physical quantities.
  • Android - It is a Linux based operating system designed Primarily for touchscreen mobile devices such as smartphones and tablets computer.
  • Algorithm - A step-by-step procedure designed to solve a problem or achieve an objective.
  • Alphanumeric A character set that contains letters, digits and other special characters such as @, $ , + . ⚹ , % . etc.
  • Archive - It provides backup storage.
  • Assembler A program that translates mnemonic statement into executable instruction.
  • Backup - Storage of duplicate files on disks, diskettes, or some other form of magnetic medium (such as tapes) as a safety measure in case the original medium is damaged or lost.
  • Backspace key - A key is used on the keyboard to delete the text. Backspace will delete the text to the left of cursor.
  • Bandwidth - The maximum amount of data that can travel in a communication path in a given time, measured in bits per second (bps) .
  • Bar Code A bar code is a machine-readable representation of information in a visual format on a surface. The first bar code system was developed by Norman Joseph Woodland and Bernard Silver in 1952.
  • Basic Input Output System (BIOS) - Also known as ROM BIOS. It provides a abstraction layer for the hardware, i.e.. , a consistent way for application programs and operating system to interact with input/output devices.
  • Binary code - The language used by computers in which data and instructions are represented by a series of 1s and 0s.
  • Bitmap A method of storing a graphic image as a set of bits in a computer memory. To display the image on the screen, the computer converts the bits into pixels.
  • Blog It is a discussion or informational site published on the world wide web.
  • Bluetooth A protocol that permits a wireless exchange of information between computers. cell phone and other electronic devices within a radius about 30 feet,
  • Booting is a bootstrapping process which starts the operating system when a computer is switched on
  • Botnet It is a collection of internets connected programs communicating with other similar programs in order to perform tasks.
  • Boot Sequence A boot sequence is the set of operations the computer performs when it is switched on which loads an operating system.
  • Buffering The process of storing data in a memory device, allowing the devices to change the data rates, perform error checking and error retransmission.
  • Bug - A software bug is an error, flaw, failure, or fault in a computer program or system produces an incorrect or unexpected result.
  • Bus - A pathway along which electronic signals travel between the components of a computer system.
  • Binary numbering system - A numbering system in which all numbers are represented by various combinations of the digits 0 and 1.
  • Chip - A tiny wafer of silicon containing miniature electric circuits that can store millions of bits of information.
  • Command - An instruction that causes a program or computer to perform a function.
  • Compiler A compiler is a computer program that -translates a series of instructions written in one computer language (called the source language) into another computer language (also called the object or target language) .
  • Communication The transmission of data from one computer to another or from one device to another is called communication.