Codes #1

I've been reading about codes and how 

they've been sent for a long time, and I'd 

like to start a series of posts dedicated to 

this because of cryptography's relation 

with maths and also because of its sheer 

content to discuss.

So, I'll be starting with basic Caesar Ciphers 

and then more in-depth material as it moves 

on. I'll also pitch in some personal thoughts 

and ideas.

All codes are basically substitution ciphers, 

where one letter is replaced by another letter, 

or number, in more complex codes.

The caesar cipher is one of the oldest codes 

ever, but still captures the fundamental idea of 

cryptography. Here's how it works:

Pick any letter in the alphabet 

other than 'a'. Then write down 

the alphabet. Below it, write 

the alphabet again, only starting 

from the letter you picked.(ex: k)-

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

K L M N O P Q R S T U V W X Y Z A B C D E F G H I J

Now that you have this, you are ready to encode!

Suppose you want to secretly message: CHEESE, 

then you check where C is, where H is, etc.

C- M

H- R

E- O

E- O

S- C

E- O

So, the message becomes MROOCO.

See if you can do the reverse and find out 

what this means: 

Led, drsc dizo yp myno sc okci dy nomyno.