Lesson 1: Computer Concepts – Part 2

Inside the System UnitPart 2

Video Expansion cards Ports

Computer Video Components

Video monitor Video controller Video driver

Computer Video The image on the monitor is composed of tiny dots called pixels.

Resolution

The higher the resolution setting, the more you can display on the monitor - but images appear smaller at higher resolutions.

Purchasing a Monitor

Features toconsider…• Screen size

• Maximumresolution

• Dot pitch

• Verticalfrequency

• Non-interlacing

Screen size is measured diagonally.

Examples of Expansion Cards

Modem Sound Video Capture Network/LAN TV Scanner

                         A video adapter card

An internal modem card

Types of Expansion Slots

PCI ISA

The system busconnects expansion

slots to themicroprocessor.

Examples of Ports

A. PS/2B. USB PortC. SerialD. ParallelE. SCSIF. VideoG. Miniplug

sH. JoystickI. Phone

JackJ. RS-14

Examples of Peripherals

KeyboardMouseMonitorPrinterScannerExternal Modem

How Modems Work

A modem takes a digital signal and converts it to sound - and vice versa

Printers

Laser Fast, higher initial cost, less cost per page

Ink Jet Slower, lower initial cost, higher cost per page

Laser printers are often used

for high volume, high quality,

black and white printing.

Surge Protector

Prevents surges in power from ruining delicate computer circuitry

Always connect yourcomputer andperipherals to asurge protector.

Photo courtesy of

Kensington Technology Group

Computer Software

Software is the logical component of a computer system.

Most software is distributed via floppy disks and CD ROMs

Do not confuse the containerwith the contents.

Floppy and CD-ROM discs are containers for software, butnot the software itself.

Computer File

A collection of data with some common purpose.

All computer software is stored in the form of files. Some computer files are programs.

Other computer files may contain work that you have

created, such as a letter or picture.

Types of Software

DataAppsOS

Software

Programs

The Operating System

Controls all basic computer functions

Lets you give simple commands to hardware.

Works with application programs to help yousave and retrieve your work

Examples of the Operating System at Work

Application Programs

Software that helps you get work done Word Writing w/ Proofing Excel Electronic Spreadsheet Outlook Email Access Electronic Filing Cabinet PowerPoint Graphic Communication

User Files

These files store work that you have performed with an application program,such as:

A letter A drawing A database of information A game you have stored to continue later

Computer Viruses

Viruses are small programs that can invisibly “infect” your system without your knowledge. Viruses can cause your computer to halt, or erase files on

the disk drives. Many new viruses are discovered every week.

Computer viruses are malicious programs created by programmers (i.e. people).

Anti-Virus Software

These programs watch all activity on your system and can detect many viruses as they try to infect the system.

As new viruses are identified, anti-virus software vendors update their software. You can usually obtain these updates over the Web.

Researching Software

Research software first Before you shop for hardware, you should always

research the software you wish to run on the computer.

Every application program has requirements for the hardware and operating system that it needs to function properly. If your computer does not meet these requirements, the application program will not run.

Purchasing Hardware After Selecting Your Software

Microprocessor Type (e.g. Pentium III) Speed (e.g. 500 MHz)

Operating System RAM Hard Drive Space Drive Options Other Hardware

Setting Up a ComputerErgonomics is the science of designing equipment to maximize your productivity and reduce fatigue.

Healthy Work Habits with Computers

Risks of computer use include: Exposure to radiation Eye strain Repetitive stress injuries

With good work habits, you can significantly reduce or eliminate these risks.

Lesson 1: Computer Concepts – Part 2