A.Codes and ciphers |
B.Differences between codes and ciphers |
C.History of codes and ciphers |
D.Inventors of codes and ciphers |
A.Ciphers can be broken or figured out more easily than codes. |
B.You could read some words in Geronimo’s letter without his trellis. |
C.The first person who ever used a cipher in history was Julius Caesar. |
D.Fondness of using codes was the hobby of the scientists in the 1600s. |
A.a piece of paper with many small holes |
B.a secret message with a lot of small holes |
C.a letter with unreadable words and sentences |
D.a sheet of paper with groups of Arabic figures |
A.military affairs |
B.commercial secrets |
C.scientific achievements |
D.personal enjoyment |