Introduction to PC Operations NC

II/Computer

Education I

Mrs. Lanie P. PlecerdaInstructor I

MS Word - Wordprocessing

MS Excel – Spreadsheet application

MS Powerpoint – Presentation

Internet – Email and search the web

Introduction

Computer – a machine that performs tasks, such as calculations or electronic communications, under the control of a set of instructions called a program.

Elements of a Computer System1. Human Resources2. Hardware3. Software

Elements of a Computer SystemHuman Resources – are required to perform

the planning, operations, and some of the controls external to the physical computer. Ex. Computer Operator, System Analyst and Computer Programmer

Hardware – refers to the physical components of a computer system or an electronic components that make up the computer system.

Software – is intangible and can only be seen but not felt. It is an instruction that tell a computer exactly what to use and what sequence of operations to perform with the data.

Major Hardware ComponentsCPU – is the heart and brain of the

computer. It allow the computer to “think” about the input given.

Memory – is classified either as primary and secondary

I/O Devices – these are devices attached to the main unit to facilitate communication (or interface) between the user and the computer.

Three Main Components of CPU1. Control Unit – which is responsible for

maintaining order among the hardware components. It acts like a traffic director; it controls and directs the flow of information between the input/output units and the central processor.

2. ALU (Arithmetic Logic Unit) – which is responsible for manipulating the data as required. It contains all the electronic circuits for performing the arithmetic calculations and logical comparisons.

3. Registers – which serve as temporary storage areas for data during processing.

Software

a. Firmware – is software stored permanently in chips in the computer’s circuitry making in unalterable by computer users.

b. Operating System – Ex. DOS, Windows XP

c. Application Software – is software that performs a specific task such as word processing, spreadsheet design or database management.

d. System Software – is software that is used to operate and maintain a computer system.

Light Pen

Light pens are electronic pointers that allow users to modify designs on-screen. The hand-held pointer contains sensors that send signals to the computer whenever light is recorded. The computer’s screen is not lit up all at once, but traced row-by-row by an electron beam sixty times every second. Because of this, the computer is able to determine the pen’s position by noting exactly when the pen detects the electron beam passing its tip. Light pens are often used in computer-aided design and computer-aided manufacture (CAD and CAM) technology because of the flexibility they provide. Here, an engineer uses a light pen to modify a technical drawing on a computer display screen.

A personal computer (PC) enables people to carry out an array of tasks, such as word processing and slide presentations. With a connection to the Internet, users can tap into a vast amount of information on the World Wide Web, send e-mail, and download music and videos. As a family tool, the PC may be used for school, research, communication, record keeping, work, and entertainment.

                                      

Computer System

A typical computer system consists of a central processing unit (CPU), input devices, storage devices, and output devices. The CPU consists of an arithmetic/logic unit, registers, control section, and internal bus. The arithmetic/logic unit carries out arithmetical and logical operations. The registers store data and keep track of operations. The control unit regulates and controls various operations. The internal bus connects the units of the CPU with each other and with external components of the system. For most computers, the principal input device is a keyboard. Storage devices include external floppy disc drives and internal memory boards. Output devices that display data include monitors and printers.

MemoryROM (Read Only Memory) – is non-volatile

since its contents are not erased when the power is off.

RAM (Random Access Memory) – is volatile, its contents are lost when power is off, thus the need for secondary storage where documents and resulting information can be stored.Primary - it is a storage which is immediately accessible to the computer.Secondary – holds data for a long period of time.

Three Basic Operations

INPUT – computer is supplied with necessary data and processing instructions.

PROCESSING/COMPUTING – the input data is processed and the answers computed accordingly to the instructions.

OUTPUT – the answers or results are reported back to the computer user.

Characteristics of a Modern Computer

1. Electronic 2. Internal storage – used for storing

both the computer program and data being processed.

3. Stored Program – the program of instructions which stipulates the sequential operations that the computer is to carry out.

4. Program modification – ability to automatically modify a program.

Advantages of Using a Computer

1. Speed – it saves a tremendous amount of time2. Accuracy – if the computer is properly

programmed and provided with accurate data, it will do the intended work with unerring accuracy.

3. Reliability – can work almost twenty-four hours a day with a little time-out for equipment check up and maintenance.

4. Retention – can store and save massive files of data and programs.

5. Economy – the per unit cost of processing data or doing computations by computer considerably lower than by alternative actions.

6. Versatility – can used to solve a wide variety of problems that arise in science and business.

Limitations of Computera. Dependence on People – it can only execute

the precise instructions that human beings provide.

b. Time-consuming and programming work – it is unproductive until it is given the program that tells it what operations to perform.

c. Disruptiveness – the results can reduced morale, alienation, confusion and even sabotage.

d. Robot-like Processing – it is a big dumb machine, dependent entirely on those who control it.

e. Computer Security – other security systems are computer controlled, responding to specific pre-recorded voice commands or physical characteristics lie handprints.

Kinds of Computer

General Purpose Computer – used for a wide variety of applications such inventory, payroll, accounting, market research and sales analysis.

Special Purpose Computer – incorporated many features of general purpose computers but support highly specialized data processing tasks. Ex. Navigational computer on an airplane.

End of Introduction