1. Computer Performance

2. Boot Process
Sequence of events that occurs between the time you turn on a computer and the time that it becomes ready to accept commands.
Power up
Start boot program
Power-on self-test
Identify peripheral devices
Load operating system
Check configuration and customization
Purpose
Run a diagnostic test to make sure everything is working.
Load the operating system, so the computer can carry out basic operations.

3. Binary Number System = 1 = 0
Computers communicate through binary language.
Also referred to as Base 2 Binary Code.
Method for representing letters or numbers using only two digits, 0 and 1.
Series of switches that can be either
On (an electric pulse is present)
Off (an electric pulse is not present)
= 1
= 0

4. Physical, touchable, material parts of a computer or other system.
Computer Hardware
Physical, touchable, material parts of a computer or other system.

5. Integrated Circuit (IC)
Another name for a chip; small electronic device made out of a semiconductor material.
Used for a variety of devices, including microprocessors, audio and video equipment, and automobiles.
Often classified by the number of transistors and other electronic components they contain.
Path from one component of a computer to another that data uses to travel.
Run between
RAM and the microprocessor.
RAM and various storage devices.

6. Silicon Chip Silicon is melted sand.
What the circuits are embedded into to keep them together.
Microprocessor integrated circuit package holds a silicon chip that contains millions of transistors and other components fabricated into the silicon.

7. System Unit Main body of a desktop computer
Consists of a metal or plastic enclosure that contains the
Motherboard
Power supply
Cooling fans
Internal disk drives
Memory modules and expansion cards
Often incorrectly referred to as the CPU, the hard disk, or the case

8. Motherboard Primary component of the computer
Holds the following items:
CPU (Central Processing Unit)
System clock circuitry
Memory
RAM (Random Access Memory)
ROM (Read-Only Memory)
“CMOS” memory
Expansion slots, used to add expansion cards (for example, Video or Sound cards)
CMOS=Complementary-symmetry/metal-oxide semiconductor

9. CPU (Central Processing Unit)
Component (microprocessor) in a digital computer
Where the actual processing takes place
Interprets instructions
Processes data contained in computer programs
Often called the brain of the computer

10. Pentium Name of the CPU. Fifth generation of the Intel processor.
Other generations
80-88
286
386
486

11. System Clock Internal Clock Clock Speed
Regulates rate instructions are executed
Synchronizes computer components
Clock Speed
Measured in units of cycles per second, which is called Hertz (Hz)
Megahertz (MHz)
Measurement used to describe the speed of the system clock.
Equal to one million cycles (or pulses) per second.
Gigahertz (GHz)
Equal to one billion cycles (pulses) per second.
1.3 GHz means that the microprocessor’s clock operates at a speed of 1.3 BILLION cycles per second.

12. Memory Where programs and data are stored while you are using them RAM
“Random Access Memory”
Provides ability for a storage device to go directly to a specific storage location without having to search sequentially from a beginning location.
Very volatile
Cannot hold data when the power is off.
Looses all data when power is lost.
ROM
“Read-Only Memory”
Drives can read data from disks, but cannot store new data on them.
One or more integrated circuits that contain permanent instructions that the computer uses during the boot process.

13. Memory Measurements Bit Byte Kilobyte Megabyte Gigabyte Terabyte
Each 0 or 1
Byte
8 bits
Kilobyte
Approximately 1,000 bytes
Exactly 1,024 bytes
Megabyte
Approximately 1 million bytes
Exactly 1,048,576 bytes
Gigabyte
Approximately 1 billion bytes
Terabyte
Approximately 1 trillion bytes

14. Input Devices Input devices supply data to a computer. Types of Input
Data: Raw facts given to the computer.
Programs: Sets of instructions that direct the computer.
Commands: Special codes or key words the user inputs to perform a specific task.
Type on the keyboard
Select from a menu
Click on a command button
User Response: User’s answer to the computer’s question.

15. Input Device Examples Keyboard Touch Pad Track Ball Scanner Mouse
Track Point
Joy Stick

16. Output Devices
Display, print, or transmit the results of processing from the computer’s memory.
Types of Output
Hard Copy: Printed on paper or other permanent media.
Soft Copy: Displayed on screen or by other non-permanent means.
Categories of Output
Binary numbers
Text documents; for example, reports and letters
Graphics; for example, charts, graphs and pictures
Multimedia; combination of text, graphics, video, and audio

17. Output Devices, cont. Monitor
Display device that forms an image by converting electrical signals from the computer into points of colored light on the screen.
Types
CRT (Cathode Ray Tube)
Flat Panel Display usually uses an LCD (Liquid Crystal Display) to display output from the computer.
Terms
Screen size: Measured diagonally (in inches) across the screen.
Resolution: Density of the grid used to display or print text and graphics. The greater the horizontal and vertical density, the higher the resolution.
Pixels (Picture Elements): Small dots that make up the image displayed on the screen. Computer display devices use a matrix of pixels to display text and graphics.

18. Input/Output Devices Printer Speakers Sound Card Modem
Output device that produces text or graphical images on paper.
Types
Ink Jet
Laser
Speakers
Sound Card
Modem

19. Storage Devices
Store your documents (data files) and programs (executable files) when they are not currently in use for processing.
Data stored on these devices does not vanish when you turn off the power to the computer.
Major categories include:
Magnetic
Solid state
Optical

20. Hard Disk
Contains disks made of metal and coated with a metal oxide that can be magnetized.
Rated by
Storage capacity, typically tens or hundreds of gigabytes.
How fast they disks spin (in rpm, rotations per minute), typically thousands of rpm.
Usually mounted inside the system unit.
Stores billions of characters of data; stated in forms of
Megabytes
Gigabytes

21. Floppy Disk
Made of flexible Mylar plastic coated with metal oxide that can be magnetized.
3.5” in size (older diskettes were 5.24”) holds 1.44 MB of data
Shutter protects the disk surface from dirt and fingerprints

22. Zip Disk Floppy disk technology developed by Iomega Corporation.
Similar in size to a floppy diskette, but thicker.
More storage capacity than a floppy; up to 750 MB

23. Flash Drive
Small, portable solid state memory card that plugs into a USB port on your computer and functions as a portable hard drive.
Fits in your pocket and can plug into any computer that has a USB drive.
Called thumb drives, jump drives, pen drives, key drives, tokens, or simply USB drives.

24. Magnetic Storage
Recording of data onto disks or tape by magnetizing particles of an oxide-based surface coating.
Fairly permanent type of storage that can be modified.

25. Digital Audio Tape (DAT)
Type of magnetic tape that uses a scheme called helical scan to record data.
DAT cartridge is slightly larger than a credit card in width and height and contains a magnetic tape that can hold from 2 to 24 gigabytes of data.
Supports data transfer rates of about 2 MB per second.
Like other types of tapes, DATs are sequential-access media.

26. Optical Storage
Means of recording data as light and dark spots on CD or DVD.
Laser beam inside the drive bounces off the disk and the sequences of pits and not-pits (Lands) is converted into ones and zeros of the data.
Pits: Dark spots
Lands: Lighter, non-spotted surface areas

27. CD-ROM Compact Disc Read Only Memory
Optical storage medium uses laser technology to read data that is permanently stored on compact disks.
Capable of storing large amounts of data—up to 1GB, although the most common size is 650MB (megabytes).
Single CD-ROM has the storage capacity of 700 floppy disks, enough memory to store about 300,000 text pages.

28. CD-R and CD-RW CD-R CD-RW Compact Disc-Recordable
Can only have its surface data changed once at each spot.
Can write multiple sessions to one disk until it is full; then it is read only.
Hold 700 MB of data.
CD-RW
Compact Disk-ReWritable
Laser beams can read, write, and erase; can be used many times (must erase before rewriting).

29. DVD-ROM
Digital Versatile Disc-Read Only Memory, or Digital Video Disc-Read Only Memory
Reads data from
CD’s; audio and data
DVD’s; data or movie
Cannot be used to write data to a disk.

30. Computer Software

31. Operating System Software
Master controller for all activities that take place within a computer; primary purpose is to help the computer system monitor itself in order to function efficiently.
Interacts with application software, device drivers, and hardware to manage a computer’s resources.
Ensures that input and output proceed in an orderly manner.

32. Platform Underlying hardware and software of the computer system.
Two popular platforms PC
Mac

33. Multitasking Running more than one program at a time.
Making sure that the instructions and data from one area of memory don’t interfere with memory allocated for other programs.

34. GUI (Graphical User Interface)
A type of user interface that features on-screen objects, such as menus and icons, manipulated by a mouse.
Abbreviation is pronounced “gooey”.

35. Definitions Program Application Software Drive
Set of detailed, step-by-step instructions that tell a computer how to solve a problem or carry out a task.
Application Software
Set of computer programs that help a person carry out a task.
Drive
A location on a network that is set aside for the collection of data.

36. Definitions Folder File Menu Icon
The subdirectory or subdivision, of a drive that can contain files or other folders.
File
A named collection of data that exists on a storage medium.
Menu
A list from which the user may select an operation to be performed.
Icon
A small picture that represents something (a file, directory, or action) in a graphical user interface.