Introduction to computer fundamentals

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Fundamentals

of Hardware and Software

INTRODUCTION

TO COMPUTER FUNDAMENTALS

Computer Studies

Computer Studies deals with the features of computers,

and the ways and methods of using the computer, so as to provide a basis for

understanding the impact of computers on individuals, organizations and our

society.

Information Technology

This is

the technology, which supports activities involving the creation, storage,

manipulation and communication of information, together with their related

methods, management and applications.

Information Technology may also be described as the integration of computing

technologies and information processing.

Hardware

Vs. Software

Hardware

These

are the physical components of a computer system that may be seen and

touched. Examples of computer hardware

are Mouse, Keyboard, Scanner, Printer, Monitor, Scanner, Plotter, etc.

Software

A set of instructions written in the

language, which the computer understands is called a program. Software may be described as programs on the

computer, which is used by the user to do a specific task/job. Software may be described as the set of

instructions that tells the computer what to do. Some examples of computer software are Corel

Word Perfect, Lotus 1-2-3, Windows '95 and '98, Solitaire, Internet Explorer,

Microsoft Office - Microsoft Word, Microsoft Excel and Microsoft PowerPoint,

ACCPAC, etc.

Computer

Vs. Computer Systems

Computer

A computer is an electronic device that is

able to perform logical, arithmetic and memory functions by manipulating

them. It is able to accept input

from the user, processes the input, stores the results of

processing and provides the user with meaningful results called output. A computer may also be described as a machine

that is under a program’s direction and control, performs four (4) basic

operations: input, processing,

storage, output. Why

is a computer so powerful? To

answer this question, the following words might come to mind: (a) Speed,

(b) Reliability, (c) Accuracy, (d)

Storage and (e) Communications.

Computer System

A Computer

System is the computer plus devices connected to the System Unit, which allows

data to be made available for processing, displaying or printing for human use.

HOW THE

COMPUTER WORKS

A computer is not able to just work on its

own without the guidance of the user. If

you want to get some information from the computer, you have to give the

computer something to process.

When you go onto the computer, and you are

ready to work, you have to give the computer something to work with. Whenever you go to the keyboard or another

input device, what ever you type or put into the computer is called Input. What is placed into the computer to be

processed is called Data. Data

can also be described also as raw materials placed into the computer to be

processed in order to get meaningful output.

When data has been accepted and processed, it has been read and

processed by the processing unit of the computer called the Central

Processing Unit. The results are

then stored for further use.

After the input has been processed and stored, output is now

available in a meaningful form. Output

is made available in two ways: Hard Copy/Permanent Copy

(information on paper or microfilm) or Soft/Temporary Copy

(information on the monitor or in the form of voice). Processed data or processed input is called

Information.

Data

Processing Cycle

This

cycle illustrates how unorganized facts (data) are converted into a more

meaningful and organized form called information.

Information Processing Cycle

A

complete sequence of operations involving data input, processing, storage and

output.

a. Input This is what you put into the

computer. Any data or instructions

entered into the

computer.

b. Processing This is the

converting/changing/manipulation of Input into a meaningful form.

c. Storage This is the keeping of processed input

for future or repeated use.

d. Output

This is the result of processing in a meaningful form. Data that has been processed

into a meaningful form.

Input

Processing Storage Output

OUTPUT

Diagram 1: Showing the relationship between the

elements of the Data Processing Cycle

Diagram 2 Showing the relationship between

Data and Information

Fundamental (Components) of a

Computer (System)

Every

computer is made up of four basic components (parts) and carry out four basic

functions. The major parts of any

computer system are: Input Devices (Keyboard, Mouse, Joystick, Scanner, etc),

Processing Devices (Central Processing Unit/Microprocessor), Storage Devices

(Random Access Memory, Read Only Memory, Magnetic Disks, Magnetic Tape, etc)

and Output Devices (Printer, Monitor, Speaker, etc).

CENTRAL PROCESSING UNIT (CPU)

This

is the logic component of the computer that interprets (understands) and

executes (carry out) program instructions (what is to be done). The Central Processing Unit is the part of

the computer that is responsible for all processing operations (of data) of the

computer. The CPU is also sometimes

referred to as the Microprocessor or Processor. The Processor is said to run the show of the

computer and is the nucleus of any computer system. This part of the computer interprets the

instructions given to it by the software, and carries out these instructions by

processing data and controlling the rest of the computer’s components. It is the most essential component that

ultimately determines the overall performance of the computer. The CPU is also described as the electronic

device that interprets and carries out instructions that operate the computer.

PARTS OF THE CENTRAL PROCESSING

UNIT (CPU)

Control Unit (CU)

Just

as the Processor is the nucleus of a computer system, the Control Unit

is the nucleus of the Processor.

The Control Unit is the functional unit of the Central Processing Unit

that is responsible for supervising the operations of the Processor (CPU). The Control Unit fetches instructions from

memory and determines their types and decodes them. Examples of the types decoded are

alphanumeric characters, numbers, etc.

The CU controls all the other parts of the computer system. Four basic operations are performed in the Machine Cycle/Processing Cycle which the CU oversees: Fetch – getting the next program

instruction from the computer’s memory, Decode – figuring out what the

program is telling the computer to do, Execute – performing the

requested action, such as adding two numbers or deciding which one of them is

larger and Write-back – writing the results to an internal register (a

temporary storage location) or to memory. The Instruction Cycle (I-Cycle) consists

of Fetch and Decode operations while the Execution Cycle (E-Cycle) consists of

Execute and Write-back operations.

Today’s advanced microprocessors can go through this entire four-step

process millions of times per second.

Functions of the Control Unit

(CU)

1.

To read and interpret program instructions

2.

To direct the operations of the internal processing component (CPU)

3.

To control the flow of programs and data in and out of Random Access

Memory (RAM)

4.

To control the flow of information to and from Input and Output Devices

Arithmetic Logic Unit (ALU)

This is the

portion of the Central Processing Unit that is responsible for performing all

arithmetic computations (additions, subtractions, multiplication,

division, etc) and logical operations on data. Examples of computations include payroll

deductions for taxes, calculating balance for bank statements and calculating

student grade average for reports. A

logical operation could be the comparison of two pieces of data, either

alphabetic or numeric. Based on the

result of the comparison, a decision can be taken from possible

alternatives/choices available.

Functions of the Arithmetic Logic

Unit (ALU)

1. To

perform arithmetic operations on data

2. To

perform logical operations on data

It is very important to

make note at this early stage that Main Memory is sometimes

classified as a part of

the Central Processing Unit.

Main Memory (MM)

This

is the memory area in which all programs and data are stored while being

executed. Main Memory is very important

to the computer because it can be written to and read from at very high

speed. Main Memory is also called Primary

Storage/Primary Memory/Immediate Access Storage. Main Memory is used to hold input data and

instructions until they are needed as well as to hold information awaiting

output. It is used to store anything,

which is actively being used by the computer at any time. Memory is used as a temporary holding place

for instructions and data.

Functions of Main Memory (MM)

1.

Stores program instructions prior to execution

2.

Stores data that can be immediately processed by the program

instructions.

3.

Stores information temporarily after processing is complete

COMPUTER TERMS

System Unit

The case that houses the computer’s internal circuitry, including the

internal processing circuitry, including the power supply, motherboard, modem,

disk drives, expansion cards, etc.

Motherboard

A large circuit board containing the computer’s central processing unit,

support chips, random-access memory, and expansion slots. Also called the Main Board.

System Clock

This component is an electrical circuit that generates pulses at a rapid

rate, measured in millions of cycles per second (MHz).

Clock Speed

The speed of the internal clock of a microprocessor that sets the pace

at which operations proceed in the computer’s internal processing circuitry.

Peripheral Device This

is a device that is connected to the System Unit. It may also be described as any external

device that is attached to the System Unit.

Examples of Peripheral Devices are Mouse, Joystick, Monitor, Plotter,

Speakers, etc.

Cyberphobia This is the irrational fear of computers

by humans.

Data This

is raw material placed into the computer to be processed. Data may also be described as what is placed

into the computer to be processed.

Information

This is processed raw material/data.

Information may also be described as processed data or data which has

been processed. Information may be

described as data that has been collected and processed into a more meaningful

form.

Registers

These are temporary storage locations in the CPU that are designed for

the purpose of storing data temporarily.

For example, one type of register stores the location from which data

was retrieved from the memory.

Hard Copy/Permanent Output This is computer output of information on

a hard/tangible medium you can see and touch.

Example of hard copy output is the output of information on paper or on

microfilm.

Soft Copy/Temporary Output This

is computer output of information on a soft/intangible medium you can see (and

hear) and not touch. Example of soft copy

output is the output of information in the form of voice or the output of

information in visual form such as output which that be seen on the Monitor

(Visual Display Unit)

Parallel Processing

The use of multiple processors simultaneously to execute a program

(instructions).

Online State of being connected to the computer (or

the Internet).

Offline

State of not being connected to the computer (or the Internet).

Additional Content:

Megahertz

(MHZ), Power supply, Integrated Circuit, Examples and types of microprocessors

– Intel Pentium, AMD, Cyrix, Duron, Athlon, etc., Multiple Processing,

S

Y S T

E M U

N I T

CENTRAL PROCESSING UNIT (CPU)

INPUT DEVICES

ARITHMETIC LOGIC UNIT (ALU)

CONTROL UNIT (CU)

E.g.

Keyboard,

Mouse, Scanner, Joystick, etc.

E.g.

Printer,

Monitor, Plotter, etc.

MAIN MEMORY

SECONDARY STORAGE/BACKING STORAGE DEVICES