This document discusses data representation and binary conversion. It covers converting binary numbers to letters using ASCII codes, using binary to create words, converting RGB colors to hexadecimal codes, and creating a secret coded message. The homework is to decode a binary message using the ASCII table, write out color codes in hexadecimal, and create and share a coded message with instructions for decoding it.

1. Data Representation
Lesson 4
1

2. Starter
Link up the foreign words to the flag of origin
2
1. Shukran
2. chnorakaloutioun
3. hvala
4. Merci
5. Danke
6. Kiitos
7. Hvala
8. Tak
9. děkuji
10. dank u
11. Tänan
12. Gràcies

3. Objective of the lesson
To be able to convert binary numbers to letters and
words.
• All of you will:
• Be able to convert binary numbers into letters.
• Most of you will:
• Use binary to create words
• Some of you will:
• Convert RGB to Hexadecimal
3

4. • Create your own way of sending a secret message
• Write a coded message
• Give instructions to decode it
4
Homework

5. Last lesson…
• You worked in teams to talk about different
areas of data representation.
• Over the next two lessons we will be focussing
on some of the important areas of data
representation.
5

6. Today
• You will decode a binary message and provide
an answer
• Use the ASCII code sheet to decode the binary
message
Step 1. Convert to ASCII values
Step 2. Convert ASCII values to letters
Step 3. Convert response back into binary
6

7. Hexadecimal
• Hexadecimal codes are used to simplify binary
codes.
• Computers do not use hexadecimal – Humans
use it to shorten Binary
• Hexadecimal is translated into binary for
computer use.
– colour references
– assembly language programs
– error messages
7

8. All Colours are created equal
• To create colours we mix together the primary
colours
• What are the primary Colours?
8
Green
Blue
Red
As we know a computer needs a
numerical value to process
RGB provides computer
scientists with a range of
numbers: 0 to 256
What is the total numbers of
colours in the spectrum?
What is the square root of 256?

9. Hex Colours
9
0 1 2 3 4 5 6 7 8 9 A B C D E F
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Hexadecimal is base 16

10. Color Decimal Code(R,G,B) Hex Code #RRGGBB
Black (0,0,0) #
White (255,255,255) #
Red (255,0,0) #
Lime (0,255,0) #
Blue (0,0,255) #
Yellow (255,255,0) #
Cyan / Aqua (0,255,255) #
Magenta / Fuchsia (255,0,255) #
Silver (192,192,192) #
Gray (128,128,128) #
Maroon (128,0,0) #
Olive (128,128,0) #
Green (0,128,0) #
Purple (128,0,128) #
Teal (0,128,128) #
Navy (0,0,128) # 10

11. Plenary
• What is the ASCII value for the letter T
• What is the ASCII value for the 01110111
• What colour is #FF0000?
11

12. • Create your own way of sending a secret message
• Write a coded message
• Give instructions to decode it
12
Homework

13. Starter
Link up the foreign words to the flag of origin
13
1. Shukran
2. chnorakaloutioun
3. hvala
4. Merci
5. Danke
6. Kiitos
7. Hvala
8. Tak
9. děkuji
10. dank u
11. Tänan
12. Gràcies
13. German
14. French
15. Estonian
16. Czech
17. Arabic
18. Bosnian
19. Catalan
20. Armenian
21. Bulgarian
22. Croatian
23. Danish
24. Finnish
25. Dutch