Binary L4
Binary cryptography challenge
Data representation: text and numbers
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Binary cryptography challenge
Data representation: text and numbers
Decode the message: KHOOR ZRUOG
Do Now
Decode the message below:
KHOOR ZRUOG
HELLO WORLD
I can decode binary messages to crack a hidden code.
Decode binary messages
Crack the code
Decode binary messages
We can use white and black dots to encrypt messages
These white and black dots represent binary numbers.
Sam
How can I convert these dots to binary numbers?
Decode binary messages
Remember, Sam, binary is a base-2 number system, so perhaps the dots represent the place values?
Lucas
Decode binary messages
◌
⚫
◌
⚫
⨉
8
⨉
4
⨉
2
⨉
1
◌
⨉
16
Sam
I can see that now. So the first row uses black dots to represent place values 1 and 4.
Decode binary messages
◌
⚫
◌
⚫
⨉
8
⨉
4
⨉
2
⨉
1
◌
⨉
16
Sam
So the first row represents 00101 in binary!
0
0
0
1
1
What is 00101 in Denary?
Decode binary messages
Sam
00101 in binary is 5 in decimal. But what could 5 mean?
5 = e
It could relate to the letter in the alphabet, Sam. So 5 would be the letter “e”.
Lucas
Decode binary messages
Decode the rest of the message!
Decode the rest of the message
Decode binary messages
Decode the rest of the message!
Decode binary messages
During WWII, German officers used a special device called an Enigma machine to encrypt all of their communications.
During World War II, Alan Turing's secret work at Bletchley Park was central to decrypting German communications.
Decode binary messages
Cryptography challenge
Crack the code
Crack the code
Principal Nezu was found unconscious in the development lab last night, hours before the Inter-Academy Crossover Festival showcase. His prototype invention — the one he was due to unveil on stage — is gone.
Eight students were in the building that night. Each decoded clue reveals one trait of whoever's responsible — age, hair colour, gender, anime — and you'll need to cross-reference every one against the suspect board.
Your job: decode the evidence, narrow the suspects, and crack the case before the showcase opens.
Fill in the blanks
Encryption is the process of converting a message
from plain text into cipher text.
Encryption is used to protect data.
During WWII, German officers used a special device called an Enigma machine to encrypt all of their communications.
During World War II, Alan Turing's secret work at Bletchley Park was central to decrypting German communications.
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