Lesson 1: Computer Concepts – Part 2

Inside the System Unit Part 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 to consider… Screen size Maximum resolution Dot pitch Vertical frequency 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 bus connects expansion slots to the microprocessor.

Examples of Ports A. PS/2 B. USB Port C. Serial D. Parallel E. SCSI F. Video G. Miniplug s H. Joystick I. Phone Jack J. RS-14

Examples of Peripherals  Keyboard  Mouse  Monitor  Printer  Scanner  External 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 your computer and peripherals to a surge 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 container with the contents.  Floppy and CD-ROM discs are containers for software, but not 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 Data Apps OS Software Programs

The Operating System  Controls all basic computer functions  Lets you give simple commands to hardware.  Works with application programs to help you save and retrieve your work

Examples of the Operating System at Work

Application Programs  Software that helps you get work done  WordWriting w/ Proofing  ExcelElectronic Spreadsheet  Outlook  AccessElectronic Filing Cabinet  PowerPointGraphic 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 Computer  Ergonomics 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