WHAT ARE COMPUTERS?

UNIT 2. HARDWARE AND OPERATING SYSTEM

What are computers?

Computers are machines that perform tasks or calculations according to a set of instructions, or programs.

Computers work through an interaction of hardware and software. Hardware refers to the parts of a computer that you can see and touch, including the case and everything inside it. The most important piece of hardware is a tiny rectangular chip inside your computer called the central processing unit (CPU), or microprocessor. It's the "brain" of your computer. Hardware items such as your monitor, keyboard, mouse, printer, and other components are often called hardware devices, or devices.

Software refers to the instructions, or programs, that tell the hardware what to do. A word processing program that you can use to write letters on your computer is a type of software. The operating system (OS) is software that manages your computer and the devices connected to it. Two well-known operating systems are Windows and Macintosh operating system.

Types of computers

Computers can be generally classified by size and power as follows, though there is considerable overlap:

• Personal computer: A small, single-user computer based on a microprocessor.
• Workstation
• Minicomputer
• Mainframe.
• Supercomputer.

The personal computer, or PC, is designed to be used by one person at a time. This section describes the various kinds of personal computers: desktops, laptops, handheld computers, and Tablet PCs.

Desktop computers

Desktop computers are designed for use at a desk or table. They are typically larger and more powerful than other types of personal computers. Desktop computers are made up of separate components. The main component, called the system unit, is usually a rectangular case that sits on or underneath a desk. Other components, such as the monitor, mouse, and keyboard, connect to the system unit.

Laptop computers

Laptop computers are lightweight mobile PCs with a thin screen. They are often called notebook computers because of their small size. Laptops can operate on batteries, so you can take them anywhere. Unlike desktops, laptops combine the CPU, screen, and keyboard in a single case. The screen folds down onto the keyboard when not in use.

Handheld computers

Handheld computers, also called personal digital assistants (PDAs), are battery-powered computers small enough to carry almost anywhere. Although not as powerful as desktops or laptops, handhelds are useful for scheduling appointments, storing addresses and phone numbers, and playing games. Some have more advanced capabilities, such as making telephone calls or accessing the Internet. Instead of keyboards, handhelds have touch screens that you use with your finger or a stylus (a pen-shaped pointing tool).

Tablet PCs

Tablet PCs are mobile PCs that combine features of laptops and handhelds. Like laptops, they're powerful and have a built-in screen. Like handhelds, they allow you to write notes or draw pictures on the screen, usually with a tablet pen instead of a stylus. They can also convert your handwriting into typed text.

EXERCISE.

1. WHAT ARE COMPUTERS?

2. WHAT IS THE DIFFERENCE BETWEEN HARDWARE AND SOFTWARE? GIVE AN EXAMPLE OF EACH.

3. CLASSIFY THE 5 TYPES OF COMPUTERS, FROM SMALLEST TO LARGEST.

4. NAME 3 TYPES OF PERSONAL COMPUTERS.

5. WHAT ARE THE MAIN COMPONENTS OF A DESKTOP COMPUTER?

6. WHAT IS THE DIFFERENCE BETWEEN A LAPTOP AND A NOTEBOOK?

7. WHAT ARE HANDHELD COMPUTERS USED FOR?

8.HOW ARE HANDHELD COMPUTERS DIFFERENT FROM LAPTOPS?

DEVICES´ DEFINITIONS

Keyboard

A computer keyboard is an input device that enables the user to enter characters (letters, numbers and symbols) into a computer. The keyboard consists of rows of keys with each key representing a different character. There are different types of keyboards available, for example, QWERTY keyboards, ergonomic keyboards, braille keyboards.

Monitor

A monitor is an output device similar to a television screen. It receives signals from the computer and displays that information for the user to view. Types: CRT, TFT, LCD, etc

Mouse

A mouse usually has between 1 to 3 buttons which users 'click' in order to point and select objects on the screen. The data from the mouse is transmitted to the computer.

A mouse is a hand held pointing device that is classed as a manual input device.

Scanner

Scanners, or computer scanners are used to transfer images or text from paper into a digital format that the computer can use. Once the information has been transferred, it can then be edited, printed, or uploaded to the Internet.There are two main types of scanner:

1. Flat-bed scanner
2. Hand-held scanner

Printer

A printer is an output device. Users can print text and pictures on to paper. A printer can also work with digital cameras to print directly without the use of a computer. There are different types of printers.

• Laser printers
• Ink-jet printers
• Impact or Dot-Matrix printers

Headphones

These are an example of an 'output device'. Headphones may be connected to the computer's sound card so you can listen to a sound file.Some headphones also have a microphone attached so you can listen and speak.

Modem

A Modem is a device used to convert digital data to analogue data in order to transmit it over the telephone network (MODulation). It will also convert the analogue data back into digital data when the computer is receiving data from the telephone network (DEModulation).

Compact Disk

A compact disc or "CD" is a flat round disc used to store data. They are used to store music and other sounds (and sometimes called an "audio CD"). A standard CD-ROM can store up to 700 Mbytes of data. As a comparison a DVD can store about 4700 Mbytes of data.

CDs come in different formats:

• CD-ROM - Read Only Memory
• CD-RW - Read Write
• CD-R - Recordable

Barcode Reader

A barcode reader, also called a price or Point of Sale (POS) scanner is a hand held input device used to capture and read information contained in a bar code. They are used in almost all modern retailers, most commonly in supermarkets.

Touch Screen

A touch screen is the only device which can be classed as both an input and an output device. It consists of a display monitor that is able to sense the location of a finger touching the screen.

Hard Disk

A hard disk is a magnetic storage device for digital data. Most personal computers contain an internal hard disk that can store large amounts of data, often hundreds of Gigabytes.

Floppy Disk

Floppy Disk This is a storage medium that can hold about 1.44Mb of data. The floppy disk has been around since the 1980's but only recently has it been largely replaced by 'memory stick technology' which can store vastly more data (1000 times more!)

Graphics Tablet

This is an input device which is often used by graphics designers and illustrators to work with images or hand drawn designs. A graphics tablet has two parts. The first part is a slender slab that lies flat on the table. The second part is a special pen. The tablet can sense how the pen is moving around on its flat surface. By moving the pen around you are able to draw lines and pictures.

Plotter

An output device. Plotters are often used by engineers, designers and architects to produce large technical drawings (often a metre wide and any length).

Tracker Ball

A point and click device similar to a mouse. A palm-sized ball is nested in a cradle and as you roll it around, the mouse pointer moves around on the screen. Popular with CAD applications.

PDA

Short for Personal Digital Assistant. A PDA is a handheld machine that lets you manage a diary, contact list, address book, 'To-Do' lists and other functions. Modern PDAs may also double up as mobile phones, email reader and (limited) internet browsing. A PDA typically consists of an LCD screen, either colour or monochrome, and some input device, such as a touch sensitve pen although some do have tiny keyboards.

Joystick

A joystick is an input device which is mostly used for playing computer games such as flight simulators.

Central Processing Unit (CPU)

A CPU (Central Processing Unit) is the core of every Personal Computer. Without it, no PC can function.

The CPU is a microchip that is installed on a motherboard and acts as the computer’s brain - performing calculations and coordinating the hardware components.

DVD

DVD is an acronym. It is a short way of saying "digital video disc" or "digital versatile disc".

DVDs can store 4.7 Gigabytes of information, while a Compact Disk can only hold 700 Megabytes.

SET SQUARE AND DEFINITION OF SKETCH/OUTLINE

TOOLS FOR DRAWING LINES

RULER

We use the ruler to measure the length of a segment. The markings on a ruler show centimeters (a long line) and millimeters (a short line).

PROTRACTOR

We use a protractor to measure and draw angles. It´s usually a semicircle with markings to show 0º to 180º.

1  SET SQUARE

Set squares are triangular “rulers” for drawing parallel and perpendicular lines.

-          A right-angles isosceles triangle (escuadra) with 45º, 45º and 90º angles.

-          A right-angled scalene triangle (cartabón) with 90º, 30º and 60º angles.

2   COMPASS

This instrument is used to draw circules and arcs, and to copy segments.

EXERCISES

Draw the following angles using the set square: 30º, 60º, 90º, 105º, 120º, 135º, 150º y 180º.

Make a pattern with circles, following these instructions:
a. Draw a straight line 15 cm long.
b. Divide into 3 segments.
c. Use each mark as the centre of a circle with 2 cm radius.
d. Draw other circles inside with 1,5 cm radius.
e. Colour the pattern.

SKETCH AND OUTLINE

Sketch in an initial drawing which shows the fundamental elements of a design and reflects its main concept.

The outline gives more specific information, including measurements, materials, ways of connecting the pieces, etc.

Vocabulary

Translate into Spanish:

-          Parallel

-          Perpendicular

-          Arc

-          Radius

-          Diameter

-          Stencil

-          Hypotenuse

-          Sketch

-          Outline

-          Freehand

-          Diagram

-          Dot

-          Measure (to)

-          Measurements

-          Material

-          Scale

-          Reduce

-          Enlarge

-          Scale ruler 

TRANSLATE INTO ENGLISH
- Angulo
- Alzado
- Planta
- Perfil derecho
- Perfil izquierdo
- Primeros auxilios
- Dibujo
- Peligroso
- Guantes
- Casco
- Señal
- Forma
- Tamaño
- Rotulador
- Goma de borrar
- Escuadra
-Cartabon
- Transportador de ángulos
- Dibujo Tecnico
- Regla
- Cinturon de seguridad

Orthographic Projection

ORTHOGRAPHIC PROJECTION

COMPUTER DICTIONARY

Hello students!!

Use www.wordreference.com

Now you have to do the following exercises:

1. On the Website, look up the following terms:

- screen - monitor - printer

- scanner - speakers - headphones

- mouse - keyboard - micropone

- Joystick - Webcam - Bar code reader

2. Classify these devices into INPUT, OUTPUT or INPUT-OUTPUT devices.

ORTOGRAPHIC PROJECTION

MAIN COMPUTER ELEMENTS

Translate into Spanish the main computer elements:

MOTHERBOARD

TECHNICAL DRAWING VOCABULARY

TRANSLATE INTO ENGLISH:


Ángulo: Angle
Dibujante: Drafter
Diseñador: Designer
Dibujo: Drawing
Perfil Izquierdo: Left Side
Perfil Derecho: Right Side
Línea: Line
Croquis: Outline
Transportador de ángulos: Protractor
Línea paralela: Parallel line
Línea perpendicular: Perpendicular line
Forma:Shape
Tamaño: Size
Escala: Scale
Escalímetro: Scale ruler
Planta superior: Top View
Dibujo técnico: Technical Drawing
Plantilla: Template
Lámina de trabajo: Worksheet
Alzado: Front View
Imagen: Image/ Picture
Regla: Ruler
Escuadra: Set Square
Cartabón: Square
Boceto: Sketch
Perspectiva: Perspective
Eje: Axis
Borde: Edge
Profundidad: Depth
Dibujo a mano alzada: Freehand
Perspectiva caballera: Cavalier perspective
Perspectiva isométrica: Isometric perspective
Perspectiva cónica:Conical perspective
Sección: Section
Escala de reducción: Reducing scale
Escala de Ampliación: Enlarging scale
Círculo: Circle
Cuadrado: Square
Rectángulo: Rectangle
Triángulo: Triangle
Rombo: Diamond
Trapecio: Trapezium
Radio: Radius
Diámetro: Diameter
Dimensión: Dimension
Altura: Height
Anchura: Width
Ancho: Wide
Calibre: Calliper
Micrómetro: Micrometer
Cubo: Cube
Elipse: Ellipse

TEAM MEMBERS IN TECHNOLOGY

1. Manager / Coordinator

2. Secretary

3. Person in charge of materials

4. Person in charge of tools

5. Person in charge of cleaning

DOCUMENTS FOR A PROJECT

Each step of a project has its own documents.

1.- SPECIFICATION

The client describes the required product or service. It´s a contract between the client and the supplier.

2.- QUOTES AND PROPORSALS

The client read the proporsals from the different suppliers and select the best one, based on cost, quality and other considerations.

3.- PLAN

The team describes the tasks and the required resources (tools, materials, human resources and time)

4.- DESIGN

5.- BIBLIOGRAPHY

It indicates where you can found information.

6.- MANUAL

7.- RECEIPT

Describes the product and indicates theh price.

PARTS OF THE TECHNOLOGY CLASSROOM

1. CLASSROOM

2. WORKSHOP

3. WAREHOUSE

4. LIBRARY

5. ICT ROOM