chapter 2

Objectives

- How Computers store and manipulate info.
-Basic Structure and organization of a comp.
-Discuss the functions and interactions of a comp system's principal internal component
-Why a comp has diff types of memory and storage devices

Basic Functions of a Computer

-Recieve Input: Accept info from outside world
-Process info: perform arithmetic on logical operations an info (Ex: google)
-Produce output: Communication info to the outside world
-Store info: move and store info in memory
-Input devices: Keyboards and pointing devices (mouse)
-Output devices: display or video monitor, printer, speaker
-CPU: the functions that process any input, output, storage, or memory
Secondary storage examples: tape, hard disk devices, recordable CD and DVD

Memory and Storage Devices

-Primary storage RAM (Random Access Memory)
-Secondary Storage: storage devices thatserve as long-term reposition for data

A Bit About Bits
Information

-communications that has valve because it informs
-anything that can be communicated, whether it has valve or not
-info. comes in many forms
-words, #s, and pics
-sound, movies
-In comp technology the terms data and info are more or less...
-comp. info is digital
-bit about binary digital
            -the smallest unit of info
            -can have 1 or 2 valves 1 or 0
            - can repeat #s, codes, or instructions
-Byte a collection of 8 bits
-using 2 symbols all #s can be represented an a calcul as well as performing arithmetic
-a calcul translates the touch on the numeric keypad into series of 0s and 1s
       - each # then is looked at as a component of its personal valves (each a power of 2)
Decimal Numbers

0 1 2 3 4 5 6 7 8 9

• each # is a column
• if you want to write 11 then it is 2 columns 1/1
• 350, 5600 all the way until 9
• certain # represent the digits

A bit about Bits cont

• using 2 symbols all #s can be represented on a calcul as well as performing arithmetic
• a calcul translates the touch on the numeric keypad into series 0s and 1s.
•               - each # then is looked at as a component of its positional values (each a power of 2).

Bits as numbers

• binary # system
• binary denotes all # w. combination of 2 digits.
• Decimal #s are automatically convertedf into binary #s & vice versa
• Binary # processing is completely hidden from the user.

Bits as Codes
    ASC 2:

• the most widely used code
• an abbreviation of American Standard Code for Information Interchange

Unicode:

• A crading scheme that supports 65,000 unique characters

Bits as instructions in Program

• Program are stared as collection of bits
• Program instructions are represented in binary notation through the use of codes

Bits, Bytes, and Buzzwork
      Bit related terminology:
              Byte   8 bytes
              Kilobyte  1 thousand bytes
              Megabytes   1million bytes
              Gigabytes    1thousand bytes
             Terabytes   1trillion bytes

Green Computing
The manufacturing of hardware and software can have an impact on the environment

• buy green equip. (Energy Star)
• Use a notebook and a solar battery
• use energy-saving features
• turn off the comp. when your away
• screen savers don't save energy
• print only once
• * recycle waste products*



gigabytes = more space on computer

CPU: Central Processing Unit
When a comp turns on it goes through all its parts. (microproccess)

• interprets and executes the instructions in each program
• Supervises arithmetic and logical data manipulations
• communicates with all the other parts of the comp. system indirectly through memory
• an extraordinarly complex collection of electronic circuits.
• Housed along w/ other chips and electronic components on the motherhood.

Compatibility

• All software is not necessary compatible w/ energy CPU
• Software written for the Power PC family of processors used in Macintosh comps won't run on intel processors
• Programs written for Linux can't run on PC's powered by Intel's microprocessor
• CPU's in the same family are generally designed to be backward compatible
• Newer proessor can process all of the instructions handled by earlier methods

Performance

• applications require faster machines to produce satisfactory results
• a comps overall performance is determined by:
•               Its microprocessor internal clock speed
•               measured in units called gigahertly (GHz) for billions of clock cycles per second
• The architecture and word size of the processor
•     High-end workstations and servers use 64 bit processors
•    Most PCs and Macintosh uses 32 bit processor
•    Same embeddded and special-purpose comps still use 8 and 16 bit processors
• Techniques for speeding up a comp's performance:
•              11 processing
•              Server cluster