This document provides an overview of computers, operating systems, and file management. It discusses types of computers including microcomputers like PCs and laptops, as well as business computers like servers and mainframes. It also describes computer hardware components, how computers work when starting up, operating systems like Windows and Linux, and concepts such as backups, uninstalling vs deleting programs, and online backups.

1. Understanding Computers, O/S, File Management

2. Types of Computers
Microcomputers
 PC or Desktop
 Laptop
 Tablet
 Netbook
 Mobile Phone or Smart Phone
Business Computers
 Servers (Help to share information like Word over all Business
computers)
 Mainframes (used in banks for massive amount of data computation)
 Supercomputer (used in large computational projects like weather
forecasting)
8/8/2012 2:09 PM 2

3. Hardware
Hardware comes with system like mouse, monitor, keyboard
 Input Device Hardware
 Mouse
 Keyboard
 Scanner
 Output Device Hardware
 Monitor
 Printer
 Speakers
 Storage Device Hardware
 Hard Drive
 External Hard Drive
 Flash Drive
8/8/2012 2:09 PM 3

4. Hard Drive
 Hard Drive has platters (plates) stacked on top of each
other and a spindle reads the platter
 Platters are covered with metal oxide that stores data
as compressions or magnetic spots on platter (e.g. tape
used in car stereo)
8/8/2012 2:09 PM 4

5. Basic Terms Answers
 BIOS (Basic Input/Output system)
 Port (outside computer that plug peripheral devices)
 CD-ROM drive, CD-R, CD-RW disk
 CPU (central processing unit)—brain of
computer/needs fan to cool it off
 Motherboard—main circuit board that has other
circuit boards on it like video and sound card
 See link on Kaboose.com for picture of Motherboard,
CPU, and BIOS
 http://resources.kaboose.com/brain/comp-les2.html
8/8/2012 2:09 PM 5

6. Pictures of parts of computer
Hard Drive Video Card
Keyboard
Monitor
Motherboard Power Supply
8/8/2012 2:09 PM 6

7. What happens when computer
starts?
 Turn on computer (boot up) or booting
 Booting is process of bringing on O/S
 BIOS (Basic Input/Output system) chip (also called ROM-BIOS because
permanent, repeated instructions) located on motherboard
 BIOS chip tells to look on hard disk for a special program called boot loader
 Boot loader is pulled into memory to start the real O/S
 Boot loader looks for kernel and loads into memory
 Kernel is interface btwn application programs and CPU, devices, and memory;
kernel can also be called manager of system resources by managing the
communication between application programs and CPU, devices, and memory
 POST test (Power On Self Test) –CPU performs check of peripheral devices on-
line like mouse, monitor, sound card, keyboard
 POST checks storage devices (have good FAT table)
 Login screen
8/8/2012 2:09 PM 7

8. What is the FAT table?
 File Allocation Table
 Table of Contents tells what sector files are located
 O/S uses FAT table to tell where files on hard drive (O/S
writes new FAT table when save file)
 A corrupted FAT table is a serious problem
 Without good FAT table O/S can’t find location of files on
hard drive
 Can use scandisk at dos prompt to fix (two FAT table (Fat1 and
Fat2); uses Fat2 to fix Fat1
 Checked in boot up process
8/8/2012 2:09 PM 8

9. What is the kernel?
 Picture of Kernel from Wikipedia
 http://en.wikipedia.org/wiki/Image:Kernel_Layout.svg#
file
8/8/2012 2:09 PM 9

10. ROM vs. RAM
 ROM stands for Read Only Memory
 Permanent memory like BIOS (hard-code instructions
on what to do when boot up computer)
 RAM stands for Random Access Memory
 Temporary memory
8/8/2012 2:09 PM 10

11. Types of CD Drives
 CD-ROM—Compact Disk – Read Only Memory
 Can only read information on disk
 CD-RW—Compact Disk Rewritable
 Can read and write on disk
 DVD (Digital Video Disc)
 Holds more information than CD
 Watch Movies or play Games
 Want to usually buy computer with DVD disc drive
 Remember DVD can play movies or CD but a CD drive
can’t play DVD
8/8/2012 2:09 PM 11

12. Bits and Bytes
 Computer reads data as switches
 Off switch is 0
 On switch is 1
 A bit is a 0 or 1 switch
 Eights bits make up a byte
 Abbreviations
 KB is about 1,000 bytes (thousand) kilobyte
 MB is about 1,000,000 bytes (million) megabyte
 GB is 1,000,000,000 bytes (billion) gigabyte
 TB is one trillion bytes or 1,024 gigabytes
 PB (petabyte) is 1015 bytes (1,000,000,000,000,000 bytes) or 1,000 TB
 Abbreviations help when knowing disk storage on hard drive when
buying software or computer
8/8/2012 2:09 PM 12

13. What types of Operating Systems are
there?
 MS-DOS
 (Eight versions that stopped making in 2000) created by
Bill Gates and put on IBM machines as PC-DOS
 Can still use by Start in search (put cmd.exe)
 Command driven copy a:*.* c:files*.*
 Linux
 Windows 3.1
 Windows XP
 Windows Vista
 Windows 7 then 8 (tablets but can put on PC)
8/8/2012 2:09 PM 13

14. Operating System
 Has Gui (gooey) interface that helps use to do tasks
like copy and paste files
 Enables multitasking so can do several tasks at once
like view e-mail and look at Web page
 Helps to manage and keep track of peripheral devices
like printers or mouse through Control Panel
 Gives users availability to do Backups and manage
fragmenting disk
 Recycle bin can recover deleted files
8/8/2012 2:09 PM 14

15. Is there a difference between Uninstall and
Deleting Programs?
 Yes
 Manually deleting doesn’t usually get all files deleted
with software installation and some files that are used
by other programs might accidently be deleted (maybe
a printer driver)
 Uninstall under Control Panel
8/8/2012 2:09 PM 15

16. Backup--System Image vs.
System Repair
 System Image backups Windows 7, hard drive (C: Drive), programs, and all files plus
system repair disc (booting up disc). System Repair Disc is included with Windows 7
Operation system and can load restore from Windows 7 installation disk or made system
repair disc. This is preferred method of backup.
 Custom backup—select what files want
 System Repair Disc is booting up disc and can make separate in case have no Windows 7
software when got computer such as laptop or netbook (may have to download or borrow
copy of Windows 7 installation disk and then use product code). The system repair disc
can be used in case have crash on Windows 7 and no way of booting. In the case of
Windows 7 not booting up, may just need to use System Repair disc to get to Startup
Repair option that will fix problems in Windows 7 and not have to do complete System
Image Recovery.
 Driver/Utility Disc (loaded device drivers like for printer that may need after install or
during restore) to get printer to work etc.
8/8/2012 2:09 PM 16

17. On-line backups
 Several companies like SkyDrive (free for limited use)
or Mozy offer on-line backup solutions
 Good in case of natural disaster
 SOS On-line backup will back up computer and
mobile phones (Android, iPhone, iPads)
8/8/2012 2:09 PM 17