Chapter 1

Chapter 1: Basic Introduction to Computers

Computers are everywhere and has become norm and almost a necessity for most of the people nowadays. So what are computer? Computer is defined as an electronic device which process information according to given instructions. For example, a computer can calculate the total amount (output) of an order (input) based on the software installed (instructions).

  Components of computers are:
1) Input device- allow users to enter data and instructions into a computer. For example, mouse used to navigate and keyboard used to input letters.
2) Output device- hardware that conveys information. For example, monitor used to display and speaker used to produce sound.
3) System unit- Case that contains the electronic components of the computer that are used to process data. For example, central processing unit (CPU) which is the core of a computer used to process the data or information.
4) Storage device- Records (writes) and/or retrieves (reads) items to and from storage media. For example, internal/external hard disk or USB flash drive used to store and read data.
5) Communication device- Enables a computer to communicate (send and receive data) with one or more computers or mobile devices. For example, modem used to transfer data between computers through telephone line.

  Advantages of using computers are:
1) Speed. A computer can perform task faster than humans.
2) Reliability. A computer will not make mistakes.
3) Consistency. A computer will not get tired therefore always getting the same results.
4) Storage. A computer can store a lot of data without "forgetting" it.
5) Communications. A computer with aid of internet can communicate with other computer around the world.

  Disadvantages of using computers are:
1) Health risks. Problems related to posture may occur and eyesight will be reduced.
2) Violation of privacy. Some personal data might be stolen by hackers.
3) Public safety. As more people uses computer, there are more data that might be stolen by hackers for unlawful purpose.
4) Impact of labour force. Some workers will be replaced by computers.
5) Impact on environment. Wastage will be created after computers life is over.

  Green computing is to reduce the impact on environment. By reducing electricity consumed and waste generated.

  Networks and Internet:
1) Network is a collection of computers and devices connected together via communication devices and transmission media. It allows the interaction between them.
2) Internet is a worldwide collection of networks. Internet can be used for communication, research and access information, shop or entertainment.

  Computer software:
1) Software is installed on a computer to tell the computer what and how to perform a task.
2) Installing is process of setting up software so that users can use it.
3) Software is developed by programmers by writing instructions in computer languages such as java to tell the computer to perform task.

  Categories of computers:
1) Personal computers. Such as desktop computer which is used for personal purposes.
2) Mobile computers and mobile devices. Mobile computers which is portable and used for personal purposes such as laptop, tablet or notebook computers. Mobile devices such as smart phones, PDAs, portable media player or digital camera.
3) Game consoles. Specifically designed for video gaming purposes. For example, Playstation, Xbox or Nintendo.
4) Server. Manages access to centralised resource or service in a network.
5) Mainframes. Is a large and high speed computers. Used primarily by large organizations.
6) Supercomputers. Is the fastest and most powerful computer.
7) Embedded computers. Is a computer that is part of larger products and only perform specific task that has been installed on it.

  Elements of information system consists of hardware, software, data, people and procedures. It is the interaction between all of those elements.

  Computer applications in society:
1) Education. Lecturers will use slideshow rather than hand writing.
2) Finance. Can be used for online banking or online investment.
3) Government. Used for performing task or interact with people using websites.
4) Health care. Used in many modern medical devices.
5) Science. Used to store data or doing research over the internet.
6) Publishing. Used to publish articles or book via internet.
7) Travel. Used for searching for information about a destination.
8) Manufacturing. Used to monitor or direct the devices used in manufacturing.