Saturday, July 17, 2010

Elements of a Computer and Communication System

A system is a group of related components and operations that interact to perform a task.

1. People
Two types of Users:

-Professionals - An Information Technology (IT) professional who had formal education in the technical aspect of using a computer and communication system. Ex. Computer Programmer.
- End-users - is someone without much technical knowledge of IT who uses computers for entertainment, education or work related task.

2. Procedure

Descriptions of how things are done, steps for accomplishing a result

3. Data/Information

Data – consists of the raw facts and figures that are processed into information.
Information – summarized data or otherwise manipulated data.

Units of Measurement for Capacity
A computer system’s data/information storage capacity is represented by:

Kilobyte (KB) equivalent to approximately 1000 bytes.
Megabyte (MB) about 1 million bytes
Gigabyte (GB) about 1 billion bytes

4. Hardware

The Basic Operations of Computing

a. Input operation – data is entered or otherwise captured electronically and is converted to a form that can be processed by the computer.
b. Processing operation – the data is manipulated to process or transform it into information.
c. Output operation – the information which has been processed from the data, is produced in a form usable by people.
d. Secondary Storage operation – data, information, and programs are stored in computer - processable form

Hardware – consists of all the machinery and equipment in a computer system

Hardware devices are categorized according to which of the four computer operations it performs.

Input Hardware - allow people to put data into the computer in a form that the computer can use.

Processing and Memory Hardware

CPU (the processor) – computing part of the computer. It controls and manipulates data to produce information.
Memory (also known as main memory,RAM or primary storage) – is a working storage. Memory is the computer’s “work space” where data and programs for immediate processing are held.

Output Hardware – consists of devices that translates information processed by the computer into a form that humans can understand.


Secondary Storage Hardware – ( external storage) – consists of devices that store data and programs permanently.
Hard Disk
Optical Disk

Four types of Computer Hardware

Input Hardware – e.g. keyboard, mouse, scanner, microphone
Processing and Memory Hardware – e.g. CPU, RAM
Output Hardware – e.g. monitor, printer, speaker, headphone
Secondary Storage Hardware – e.g. hard disk, diskette, optical disk or CD, flash drive

5. Software
Software or programs – consist of the step by step instructions that tell the computer how to perform a task.

Two Major Types
Application software
System Software

Application Software – defined as software that can perform useful work on general purpose task.

Web browser, word processing software, spreadsheet software, database software, presentation graphics software. 1) Opera (Web Browser) 2) Microsoft Word (Word Processing) 3) Microsoft Excel (Spreadsheet software) 5) MySQL (Database Software) 6) Microsoft Powerpoint (Presentation Software) 7) iTunes (Music / Sound Software) 8) VLC Media Player (Audio / Video Software ) 9) World of Warcraft (Game Software) 10) Adobe Photoshop (Graphics Software)

Application software run under System Software , and are made to do a specific task

System Software - have direct control and access to your computer hardware , and memory locations . They perform I/O operations on various memory locations , and control the hardware , to make the application software do a task.

Operating systems , are the main examples for system software . Examples : 1) Microsoft Windows 2) Linux 3) Unix 4) Mac OSX 5) DOS 6) BIOS Software 7) HD Sector Boot Software 8) Device Driver Software i.e Graphics Driver etc 9) Linker Software 10) Assembler and Compiler Software

6. Communication

Communication – defined as the electronic transfer of data from one place to another.

1 ) sender
2) receiver
3) computer
4) transmission medium
5) signal converter - modem