INTRODUCTION TO COMPUTERS

• The personal computer was far from reality in 1968. Computer users were limited to specially trained operators and engineers.

• No one ever anticipated that today every office worker must work with computers and most people use computers in their everyday lives – both at home and at school.

• It is important to learn about the parts of a computer, how a computer operates, and different tasks the computer can perform.

• It is equally important to learn how the computer you are using today has evolved and how it can give you access to one of the greatest sources of information - the internet.

BRIEF HISTORY OF COMPUTERS

Early 1800’s 1886 1944_/___________________/______________/______________Machines could be programmed. The operation was controlled by cards with holes punched in them.

A punch card machine was developed that could be used with electricity

IBM invented a 50-foot –long, 8-foot-high machine that was able to add, subtract, multiple, divide, and refer data tables using punched cards.

http://www.wired.com/science/discoveries/news/2008/08/dayintech_0807

BRIEF HISTORY OF COMPUTERS

1945 19471948_/____________________/____________________/______A machine was

created for the US Army that could do calculations a thousand times faster than earlier devices. It weighed about 30 tons and covered about 1,000 sq. feet of floor space.

A method for storing programs electronically was developed. Before this, computers were wired to perform only certain tasks. To change a task, the computer would have to be required.

The first machine to be called a computer

was completed.

BRIEF HISTORY OF COMPUTERS

1951 1975 Today_/________________/________________________/_________

The first commercial computer was completed. Eight of them were sold.

1. Steve Jobs started Apple Computer in his garage.

2. Bill Gates established Microsoft.

Today’s computer is a direct result of Apple and IBM in hardware and software development. Today’s computers have thousands of times more the capability and are sold at a fraction of the cost than those of the much larger computer system years ago.

WHAT IS A COMPUTER?

Input a. accepts data

The Information Processing Cycle

Processing b. processes data

Output c. produces output

Storage d. stores results

A computer is an electronic device that executes the instructions in a program. (An electronic device that does what it is told)

SOME BEGINNING TERMS

1. Hardware Physical parts of the computer.

2. Software` Programs (instructions) that tell the computer what to do.

3. Data individual facts, like first name, price, and quantity.

4. Information Data which has been massaged into a useful form, like a complete

mailing address.

5. Default Original settings

Speed A computer can do billions of actions per second.

Reliability

Failures are usually due to human error, one way or another. (Blush for us all!)

Storage A computer can keep huge amounts of data.

                                                                             

What makes a computer powerful?

HOW A COMPUTER SYSTEM WORKS

• Data is entered into the computer

• The computer processes the data and displays the desired information.

• A software program – a detailed set od computer instructions that resides in the computer, tell the computer what to do.

• There are two types of software• System program software – controls the way computer parts

work together• Application program software – Tells the computer to perform a

specific task.

TYPES OF COMPUTERS

• Computers vary in type, size, speed and capability.

• PC (personal computer) – The most common type of computer. Found in homes, offices and schools.

TYPES OF COMPUTERS

• Supercomputer – The fastest type of computer. Used only by government agencies, education institutes and larger corporations.

• Mainframe – Less powerful than supercomputers but capable of storing and processing large amounts of data. Used by universities, medical institutions and banks.

• Smartphones, Tablets, Netbook,

COMPUTER MEMORY

• The memory of a computer is comprised of circuits that are contained in tiny computer chips. The number of memory locations is states in terms of bytes.

• Byte – a unit of storage capable of holding a single character. A byte is equal to 8 bits. Large amounts of memory are indicated in terms of kilobytes (KB), megabytes (MB), and gigabytes (GB).

• Every computer comes with certain amounts of physical memory, referred to as main memory of random access memory (RAM).

• Read only memory (ROM) is computer memory on which data has been prerecorded. This data can only be read, it cannot be deleted.

• ROM is different from RAM because it remains even when the computer is shut down. PCs contain ROM memory that stores critical programs, like those needed for system start-up.

PARTS OF A COMPUTER

• Hardware is made of four main units: input devices, output devices, processing unit, storage devices.

• Input Devices: Transports data into the computer.• Keyboard, mouse, touch pad, scanner, digital

camera, microphone.

• Output Devices: Allow the user to see or hear the information the computer compiles.

• Printer, monitor, speakers.

A computer is made up of hardware and software

HARDWARE CONTINUED

• Processing Unit: CPU. Contains the computer chips and circuits that control and manipulate data to produce information.

• Storage devices: Allows the instructions and data to be saved. • Hard drive – internal storage device• Floppy Disk – • CD-Rom – • Flash Drive -

SOFTWARE

• Software is a set of instructions written by programmers in a machine language that tells the computer what to do, how to do it, and how to perform certain tasks based on input from the user.

• The words software, program and application are used interchangeably.