How can you and your friends share a secret?
in a code or a cipher
In a code how is each word written?
as a secret code word
What is done in a cipher?
In a cipher each letter is changed.
Have codes and ciphers been important in history?
yes
What Roman used a cipher to send messages to his troops?
Julius Caesa
Whose spies used code during the American Revolution?
George Washington's
What did the Americans do to Japan's code in Word War II?
they broke them
After breaking the code what were they able to do?
they  got enough information to destroy a powerful Japanese fleet.
What do storekeepers use codes for?
to mark their goods
What do those codes show about payment?
how much is paid for the goods
What do they display about inventory?
when they are added
Who uses this method to conceal things from their rivals?
Businessmen