SCL 3 : OPERATING SYSTEM AND FILE MANAGEMENT

Question 1 : List down all the operating system used in a desktop/laptop today and find good descriptions of how operating system works? Hence, state their advantages and disadvantages.

These are some of the operating system used in desktops/laptops :

• Microsoft Windows

• Advantages
• easy to use
• Many selection of software available
• Compatible with (supports) new hardware
• Compatible with MS driven websites

• Disadvantages
• high resource requirements
• low security protection
• has closed source
• additional expenses
• has to deal with many license agreements

• Mac OS
• Advantages
• highly protected from viruses
• high performance at high speed
• user-friendly
  
• Disadvantages
• expensive
• less hardware choices
• less compatibility with softwares

• UNIX 
  
• Advantages
• efficient virtual memory
• can multitask with protected memory
• available on wide variety of machines
  
• Disadvantages
• not user-friendly
• commands has to be detail
• user has to understand main features to use UNIX

• Linux
  
• Advantages
• Easy to install
• System rarely crash (stable)
• Less vulnerable to computer malware
  
• Disadvantages
• most Windows program cannot run in Linux
• smaller selection of peripheral hardware drivers
• less user-friendly (especially to newbies)

An operating system works in the middle of software and hardware. The instruction or command given by a user through a software is passed to the operating system. The operating system allocates memory from the RAM and gives that instruction to the CPU for executing it. In a computer, programs are divided into high, medium and low priority. The instructions are executed according to these priorities. In example, in Microsoft Windows operating system, Task Manager is given a high priority and that is why it opens even when explorer is crashed.

SCL 3: OPERATING SYSTEM AND FILE MANAGEMENT

Question 2: Nowadays, even smart phones have their unique operating system. Draw a table of comparison between the two most popular OS in smart phones, which are Android and Windows 8.

Smart Phones Operating System (OS)

Differences	Android	Windows 8
The Store	Google Play	Windows Phone Marketplace
Integrated Development Environment (IDE)	Eclipse, JVM is required	Visual Studio 2012 Express, Windows 8 pro/Enterprise x64 version is required
Emulator	Slow, but Google is making a good progress with snapshot option and hardware acceleration for new machines. Also, there is an open source project called Android x80 which runs very fast under a virtual machine and could be an amazing alternative to the emulator.	Fast, it uses hyper-v for virtualisation. That gives a good impact on its responsiveness.
UI Design	Design in Android is not appreciated by developers, you have to write a lot of XML to get what you need, the drag and drop tool is not that good.	Well designed, uses new graphic style called modern UI Design

SCL 2 : COMPUTER SOFTWARE

QUESTION NUMBER 2

Discuss different types of threats and malicious program (malware) that can damage a computer, mobile device or disrupt any system.

Search for information on current known malware program. Based on the information that you have found, create a table to list different types of malware, what it does and how it can be repaired or removed. These information is useful for you to prevent any malware from damage your computer system.

TYPES OF MALWARE	WHAT IT DOES?	HOW IT CAN BE REMOVED OR REPAIRED?
Trojan Horse	~ Trojans can delete data, compromise security, relay spam or porn, and otherwise infect your computer.	~ It can be repaired or removed by using Trojan Horse virus removal tools. ~ It scans Windows PC and remove virus automatically. ~ Examples, Emsisoft Anti-Malware
Virus	~ The virus destroys data or looks for things like passwords, credit card numbers, or other sensitive data. ~ A virus can also use your computer to relay spam email or to coordinate attacks against websites on the Internet.	~ Run your virus-scanner. ~ Use a reputable anti-virus such as Avira AntiVir, AVG and Avast. ~ Reboot into “Safe mode with Networking”.
Worm	~ A worm is a virus that replicates itself over a network. ~ Worms often arrive via email, peruse your address book and send a copy of themselves to others in your address book, masquerading the message as though it’s from you. ~ Worms are used to deliver viruses or the worm itself might be a virus.	~ Worm can be removed with the help of effective anti-virus products like Symantec Norton AntiVirus, Kaspersky Anti-Virus, McAfee VirusScan and AVG Anti-Virus.