## Introduction: Caesar Cipher

A quick, and useful tool for basic encryption. The Caesar Cipher makes a fun game too!

## Supplies

- A protractor.

- A ruler.

- A large sheet of cardboard.

- A pin.

- A utility knife, or scissors.

- A cat, for testing if your cipher works.

## Step 1: Measure the Two Circles.

Use your protractor, and measure out a six-inch radius for a total 12-inch diameter circle. Then, measure out a five-inch radius with a 10-inch diameter circle. Finally, cut out the two circles from the cardboard.

## Step 2: Attach and Divide the Two Circles

Take the two circles and insert the pin in the middle of the two circles, attaching them and folding the legs back. Now, mark a line in the middle, then on the other side. Keep dividing and marking until you have 32 sections.

## Step 3: Filling in the Numbers and Letters

Finally, fill in each section with A-Z. With the extra sections, add in the numbers.

Great! You're done, have fun with your Caesar Cipher!

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## 2 Comments

3 years ago

The Caesar cipher is very simple to break, once you have deciphered one letter the rest are automatically known. You could make the cipher more difficult to break by scrambling the order of letters on one wheel. And why only the numbers 1 - 6 ? It is easy to divide the circle into 36 sectors using a protractor, each sector is 10 degrees.

Reply 3 years ago

Hi kymyst,

Yes, I know this is the most basic Caesar Cipher, and thank you for the insight for making it more complex. When I made this, I didn't have an actual protractor on hand, so I just divided it that way.