Chapter 2 Objectives

*basic structure

*organization of comp

What Computers Do

*Receive input - accept information outside world

*Process information - decision making

* Store information: move/store info.

Input Devices - keyboards
Output devices - printer, speakers
Central processing Unit (CPU) - processes input

Memory and Storage Devices
*Primary storage RAM (Random Access Memory)
*Secondary storage: storage devices that serve as long-term repositories for
data
**hard disk devices
**CD/DVD
**tape drivers

Info
*communication that has value b/c it informs
**anything that can be communicated whether it is valuable or not
**words, numbers, pictures
**sound, movies

Computer info is digital
**Byte = 8 bits

Steps in the Scientific Method
*Multitasking
*Science Project, regular project
You go through the following steps:

1. problem
2. hypothesize data
3. analyze
4. scientific
5. conclusion

Question is identified
--hypo
--data sought/gathered
--hypo tested/evaluated
--reliable conclusion

Critical Thinking

-correct thinking in the pursuit of revelant/reliable knowledge about the world

(think critic-does what)

- ask appropriate?

- gather info
- efficiently/creatively sort info
- reason info
- come to conclusion

      

                                                                                                                          

Bits as Numbers

    Binary number system   

How Binary works

0 1 2 3 4 5 6 7 8 9

 

10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 20

 

Binary uses two digits, each column is worth the twice the one before.

 

To convert binary to decmimal WRITE IN EXPANDED NOTATION

 

Binary to Decimal SOLUTION; use Microsoft Windows Calculator

• binary denotes all the numbers with combination of two digits
• decimal numbers are automatically converted into binary numbers and vice versa
• binary number processing is completely hidden from the user

decimal representation- binary representation
0-0
1-1
2-10
3-11
4-100
5-101
6-110
7-111
8-1000
9-1001
10-1010
11-1011
12-1100
13-1101
14-1110
15-1111

Bits as Codes

ASCII

the most wideley used code
an abbreviation of American Standard code for Information Interchange

Unicode

A coding scheme that supports 65,000 unique characters

Bits as Instructions in Programs
-->Programs are stored as collections of bits
Program instructions are represented in binary notation through the use of codes

Bits, Bytes, and Buyzzwords
byte=8 bits
kilobyte= 1 thousand bytes
megabytes= 1 million bytes
gigabytes= 1 billion bytes
terabytes= 1 trillion bytes

Green Computing

The manufacture of hardware and software can have an impact on the environment.
-- buy green equipment (energy star)
--Use a network and solar battery
-- turn off the computer when you're away
--screen savers don't save energy
--print only once
 --recycle waste products