1. Binary System

2. What is it?
Definition - a positional system of numeration that uses binary digits and a radix of 2 (source - Dicitonary.com)
What does that mean?
Things are composed of a collection of binary digits or, as they are more commonly called, bits.
Bit - the smallest unit of information on a machine(source – webopedia)
A bit can only hold two values (0 or 1)

3. What are some other examples?
BLACK or
STOP or GO
HEADS or TAILS
Can you think of a device in the classroom other than the computer that is binary?
White

4. Why it is used in computers
Since modern day computers are electrical devices, a 0 and 1 can be easily represented using ground and a positive voltage.

5. What’s in there? Pictures Text Numbers Sounds People Places Email
Papers
Journals
Recipes
Numbers
Sounds

6. Going from 0/1 to Pictures
How do we go from black and white to complex pictures?
Pictures are composed of a grid of small boxes called pixels.
By using a greater number of pixels, we can draw more detailed pictures!

7. Scale 1x1 3x3 5x5 10x10 1 pixel 9 pixels 25 pixels 100 pixels
Now you try drawing a house in each grid on your worksheet.

8. Where does it end?
564x750
423,000 pixels

9. What about text?
First we divide text into words and then to single characters (A,B,C,X,Y,Z)
Then we use a code(index) to assign a specific collection of bits to that character
One of the more common sets used is ASCII which uses 7 bits and has a total of 128 characters

10. For example… THE CAT IN THE HAT Take out CAT
Then split it up into its individual characters:
C –
A –
T –
So CAT would read:

11. Numbers What we know – Decimal System 0,1,2,3,4,5,6,7,8,9
What we have to work with in the Binary System: 0,1
Luckily for us, mathematical operations work much the same way in both

12. Counting Decimal – Binary – 0,1,2…9,10,11…19,20,21…99,100,101
0,1,10,…..

13. Addition
Decimal:
= ?
Binary:
= ?

14. Homework
2nd Handout
Write out your name in binary code on a piece of paper.