Intro to Computer Hardware

Mr Arthur

Aims of the Lesson 1

1. To discuss computer hardware and software

2. To examine the difference types of Input and Output devices

3. Quickly finish folder labels and print

4. Research different input and output devices

Computer Systems

Hardware All the Physical parts of a Computer System (the

bits that you can see and touch) Software

Software is a collection of programs that help the computer hardware to work properly

The Computer System

Input Devices

Processor

CPU

Output Devices

Backing Storage Devices

Main Memory

RAM and ROM

Aims of the Lesson 2

1. To discuss the different input devices we looked at last period

2. To discuss the different output devices

3. To identify the characteristics of different output devices

Input Devices

Keyboard Graphics Tablet Touch-Sensitive Screen Mouse Microphone Digital Camera Digital Video Camera Webcam Trackball Trackpad Joystick Scanner

The Physical Parts of a Computer The Physical Parts of a Computer System which allows data to be System which allows data to be entered into a Computer Systementered into a Computer System

Output Devices An output device is a device

which allows data to be displayed or passed out of a computer system

Printers Laser Inkjet

Monitor Liquid Crystal Display Thin Film Transistor Cathode Ray Tube

Plotter Load speaker Projector

Laser Printer

A laser printer uses a laser beam to project the image of a page on to a photosensitive drum. It then attracts toner by means of an electrostatic charge before transferring it to paper.

Inkjet Printer

Inkjet printers produce printouts by firing tiny drops of ink at the paper. Each drop makes up part of the letter or picture.

They produce good quality printouts and can print onto plastic and CDs.

Most modern inkjet printers hold 2 ink cartridges, one with black ink and one with colour

Comparison of Printers

Printers are usually compared in relation to 3 different factors

Resolution A Printers accuracy is known as its resolution.

Resolution is measured in dots per inch Speed

The speed of a printer is measured in pages per minute (PPM)

Cost Capital cost is how much it costs to buy the printer The Running cost is how much it costs to use the printer

Comparison of Printers

Type of Printer

Speed Cost Noise Quality

Dot-matrix Slow Cheap Noisy Poor

Ink jet Medium Mid Quiet Good

Laser Fast Expensive Very Quiet Very Good

Aims of the Lesson 3

1. To revise the different Output devices

2. To revise characteristics of printers

3. To introduce backing storage devices

4. To discuss different storage capacities

Backing Storage

We require backing storage to store programs and files

Without backing storage all our data would be lost when we turn the computer off

Backing Storage Media

Magnetic Tape

Floppy Disk

Hard Disk

CD-ROM

DVD-ROM

CD-Rewriteable

CD-Recordable

DVD-Rewriteable

DVD-Recordable

USB Flash Pen

Storage Capacities

1 bit = on or off

8 bits = 1 byte

1024 bytes = 1 kilobyte

1024 kilobytes = 1 megabyte

1024 megabytes = 1 gigabyte

1gb 1.3 mb

Aims of the Lesson 4

Last Lesson• To revise characteristics of printers• To revise backing storage devices

Today’s Lesson• Begin the Word Processing Unit

Aims of the Lesson 5

Last Hardware Lessons• To revise input devices• To revise output devices• To revise characteristics of printers• To revise backing storage devices

Today’s Lesson• To discuss the processor• Parts of the Processor

The Computer System

Input Devices

Processor

Central Processing

Unit

Output Devices

Backing Storage Devices

Main Memory

RAM and ROM

The Processor

The processor or Central Processing Unit is the brain of the computer

The performance of the processor is measured in Giga Hertz (GHz)

We send programs to the processor to get the computer to do something

Aims of the Lesson 6

Last Hardware Lessons• To revise input devices• To revise output devices• To revise characteristics of printers• To revise backing storage devices• Processor• Parts of processorToday’s Lesson• Main Memory

• RAM / ROM

RAM and ROM

Main Memory The Main Memory of a

computer is used to store programs and data

The processor cannot store the whole program and needs its main memory to store parts of the program

Types of Main Memory Random Access

Memory Where programs is

stored temporarily while the computer is on

The contents of RAM is lost when the computer is switched off

Read Only Memory Where data and

programs are stored permanently