secretcodes tcm4 336597

Information about secretcodes tcm4 336597

Published on December 31, 2007

Author: Sudiksha

Source: authorstream.com

Content

Slide1:  Ever wanted to send a message but not let anybody else know what you are saying? For thousands of years people have been doing just that. They do it using codes. Slide2:  The ancient Egyptians and Greeks used codes to create secret messages. Mary Queen of Scots sent letters in code. During World War II the Nazis used the Enigma code machines to encipher their messages. Allied mathematicians and cryptographers worked on breaking the Nazi secret codes. They were able to build replicas of the German Enigma machine which they used to decipher Nazi radio messages. Enigma Machine Slide3:  One of the easiest codes you can use is the ‘alphabet up one’ code. This is when you want the letter A but use the letter B instead. If you want B, you would use C. For C - use D and so on up until Z which moves up one to become A. Slide4:  Here is a grid to explain how the code works: A B C D E F G H I B C D E F G H I J J K L M N O P Q R K L M N O P Q R S S T U V W X Y Z T U V W X Y Z A If you break this code - ZPV XJMM VOEFSTUBOE UIJT NFTTBHF Slide5:  You can use the ‘alphabet up two’ code or the ‘alphabet back one’ code. You can use any code you like as long as the person receiving the message knows what code you are using. You should make a grid for the ‘alphabet up two’ or the ‘alphabet back one’. When you have done this, you should write a message for a friend. See if they can understand what your coded message says. Slide6:  Another famous code is the ‘numbers for letters’ code. In this code we use 1 instead of A, as A is first in the alphabet. We use 2 instead of B, as B is second in the alphabet….. and so on all the way up to 26 instead of Z, as Z is the twenty sixth number in the alphabet. 3 - 1 - 14 25 - 15 - 21 6 - 15 - 12 - 12 - 15 - 23 20 - 8 - 9 - 19 Slide7:  If you make things really difficult for codebreakers, you can combine the two codes and do the ‘alphabet up one + numbers for letters’ code. Instead of A we use B …. but B is second in the alphabet, so A becomes 2. B moves up one to C but C is third in the alphabet and so on. This is not easy, so the best thing to do is write out a grid. A B C D E F G H I 2 3 4 5 6 7 8 9 10 J K L M N O P Q R 11 12 13 14 15 16 17 18 19 S T U V W X Y Z 20 21 22 23 24 25 26 1 Notice that Z moves up in the alphabet to A, so becomes the number 1 Slide8:  Playing with codes is great fun. Be careful that you don’t make up a code that is so difficult to break that nobody can work out what you are saying. REHTONA SUOMAF EDOC is the back to front code. This is where the words are all spelled back to front. If I want to use the word SPY, I reverse the letters and get YPS. Slide9:  If you are really good with codes, you can do complicated things like replace the letters of the alphabet with numbers but do it in reverse order. Slide10:  A is the first letter of the alphabet but we will use the number 26 B is the second letter of the alphabet but we will use the number 25 We continue this pattern all the way up to the letter Z Z is the twenty sixth letter of the alphabet but we will use 1 A B C D E F G H I 26 25 24 23 22 21 20 19 18 J K L M N O P Q R 17 16 15 14 13 12 11 10 9 S T U V W X Y Z 8 7 6 5 4 3 2 1 12 – 13 – 15 – 2 22 – 3 – 11 – 22 – 9 – 7 – 8 24 – 26 – 13 24 – 9 – 26 – 24 – 16 7 – 19 – 18 – 8 24 – 12 – 23 - 22 Slide11:  Squared number codes: Do you know your squared numbers? If you square the first ten numbers, you get: 1 4 9 16 25 36 49 64 81 100 Can you tie squared numbers to the letters of the alphabet to create the squared number code? A = 1 B = 4 C = 9 … Slide12:  A B C D E F G H I 1 4 9 16 25 36 49 64 81 J K L M N O P Q R 100 121 144 169 196 225 256 289 324 S T U V W X Y Z 361 400 441 484 529 576 625 676 400 – 64 – 25 16 – 81 – 196 – 196 – 25 – 324 144 – 1 – 16 – 625 81 – 361 1 361 – 256 – 625 Slide13:  Although this looks quite difficult, the first thing a good code breaker would notice is that all the numbers are squared numbers. When you spot this, breaking the code becomes much easier. The first thing a good code breaker looks at is the set of numbers and if they can spot that all the numbers are even, odd, squared, prime or members of any other set of numbers, they know where to start when breaking the code. 28 – 30 – 46 26 – 2 – 22 – 10 50 – 30 – 42 – 36 30 – 46 – 28 6 – 30 – 8 – 10 – 38

Related presentations


Other presentations created by Sudiksha

3 Theodore Roosevelt
22. 10. 2007
0 views

3 Theodore Roosevelt

ramasetu24june200747 69
30. 09. 2007
0 views

ramasetu24june200747 69

08 Tornado
05. 10. 2007
0 views

08 Tornado

ACEI New Orleans 2004
05. 10. 2007
0 views

ACEI New Orleans 2004

Breaking Bad News May 07 ASA
08. 10. 2007
0 views

Breaking Bad News May 07 ASA

DESIGNING A TEMPERATURE SENSOR
12. 10. 2007
0 views

DESIGNING A TEMPERATURE SENSOR

blackhole
07. 10. 2007
0 views

blackhole

quiz
10. 12. 2007
0 views

quiz

BSRUN
19. 10. 2007
0 views

BSRUN

E consultancy slides march 6th
25. 10. 2007
0 views

E consultancy slides march 6th

breakinggridlock0612 01
30. 10. 2007
0 views

breakinggridlock0612 01

EXPLORERS
01. 11. 2007
0 views

EXPLORERS

Japanl
09. 10. 2007
0 views

Japanl

oct16 gfbiedu
25. 10. 2007
0 views

oct16 gfbiedu

dbirday croft
16. 11. 2007
0 views

dbirday croft

KSA V5
23. 11. 2007
0 views

KSA V5

DavidShipman
04. 10. 2007
0 views

DavidShipman

Significance
25. 10. 2007
0 views

Significance

NASA
03. 01. 2008
0 views

NASA

Day 3 Charlotte DUFOUR TIPS
04. 12. 2007
0 views

Day 3 Charlotte DUFOUR TIPS

colangelo
07. 01. 2008
0 views

colangelo

pisa overview
17. 10. 2007
0 views

pisa overview

NG21A 07 Rundle
30. 10. 2007
0 views

NG21A 07 Rundle

McCarthypix
02. 11. 2007
0 views

McCarthypix

frital
24. 10. 2007
0 views

frital

Ammosov RPC IHEP
12. 10. 2007
0 views

Ammosov RPC IHEP

P4 2 Kawagoe
15. 10. 2007
0 views

P4 2 Kawagoe

PE Minerals
16. 02. 2008
0 views

PE Minerals

Internal Analysis Lecture
24. 02. 2008
0 views

Internal Analysis Lecture

OSHAtop102006
26. 02. 2008
0 views

OSHAtop102006

T E of the Machine Gun
27. 02. 2008
0 views

T E of the Machine Gun

1960s
20. 02. 2008
0 views

1960s

Porteous
12. 03. 2008
0 views

Porteous

AG 2002 11 16
24. 10. 2007
0 views

AG 2002 11 16

Md  Ppt
24. 03. 2008
0 views

Md Ppt

science genetics
03. 10. 2007
0 views

science genetics

Grade 9 Heat
03. 04. 2008
0 views

Grade 9 Heat

Final Prelims 2006
16. 04. 2008
0 views

Final Prelims 2006

FOP01 Franchise Opportunity
17. 04. 2008
0 views

FOP01 Franchise Opportunity

pres4
18. 04. 2008
0 views

pres4

LSE
22. 04. 2008
0 views

LSE

B1
30. 10. 2007
0 views

B1

OPC Notes CT
07. 05. 2008
0 views

OPC Notes CT

chris corrigan pres
30. 04. 2008
0 views

chris corrigan pres

Facility Layout Lecture Notes
02. 05. 2008
0 views

Facility Layout Lecture Notes

Sukal Linger Presentation
08. 10. 2007
0 views

Sukal Linger Presentation

access programme 2004
17. 10. 2007
0 views

access programme 2004

SuperValu Presentation2
02. 10. 2007
0 views

SuperValu Presentation2

Larsen
07. 03. 2008
0 views

Larsen

cbm39 269
14. 04. 2008
0 views

cbm39 269

Cuban
23. 12. 2007
0 views

Cuban

ICN2001 Final Report for web
20. 03. 2008
0 views

ICN2001 Final Report for web

map ftaa windows xp
22. 10. 2007
0 views

map ftaa windows xp

The Motorola Phone Comedy
17. 10. 2007
0 views

The Motorola Phone Comedy

PresSchatanIntrod
22. 10. 2007
0 views

PresSchatanIntrod

ERCIMgridasiaRR
16. 10. 2007
0 views

ERCIMgridasiaRR

bpesp
23. 10. 2007
0 views

bpesp

Florida Congress 6 06
22. 10. 2007
0 views

Florida Congress 6 06

WrinkleInTime
24. 10. 2007
0 views

WrinkleInTime

WNVEnterpriseGIS Chicago
21. 10. 2007
0 views

WNVEnterpriseGIS Chicago

pira ing
04. 10. 2007
0 views

pira ing

SolarHeliosphere
11. 03. 2008
0 views

SolarHeliosphere

04ift tomatosalsaPoster combined
04. 03. 2008
0 views

04ift tomatosalsaPoster combined

InstallingPortlets
05. 10. 2007
0 views

InstallingPortlets