Here you can find extra materials and further information on the topics presented in this website. You can also find attributions for resources used and referenced throughout the website.

Website Idea

CryptoCompanion was originally an app created in App Inventor for the AP Computer Science Principles' Create Task.

CryptologyCompanion .aia File

Website Logo

The website logo was created on Inkscape.


Fonts were sourced from Google Fonts. This is Anaheim, by Vernon Adams.

All Google Fonts are open sourced and free for use. This is Roboto, by Christian Robertson.

Main Page

The image of Andrew Zhou was taken by himself. The logo of the 2017 Pennsylvania High School Computer Fair was created by Brynna Tressler from Danville Area High School.

Caesar Cipher

The two images of the Caesar Cipher and ROT13 are taken from Wikipedia. The image of the Caesar Cipher shift has been released to the public domain by its creator Matt_Crypto and is available from Wikimedia Commons. The ROT13 photo has also been released to the public domain by its creator, Benjamin D. Esham. It is also available on Wikimedia Commons.

Wikipedia Article on the Caesar Cipher
Wikipedia Article on ROT13

Simple Substitution Cipher

The graph of frequencies is available open souce on Wikimedia Commons. It was created by Nandhp.

Both The Gold-Bug and The Adventure of the Dancing Men were released before 1923, and therefore fall under the public domain.

Wikipedia Article on Simple Substitution

Vigenère Cipher

The Vigenère chart is avaliable open source on Wikimedia Commons. It was created by Brandon T. Fields.

Wikipedia Article on Vigenère


The video was taken from YouTube. It was created by the user Tom Scott.

Tom Scott's Statement: If you're just embedding the original YouTube player in your own site, go ahead: you don't need to ask!

Tom Scott's website
Tom Scott's Youtube Channel

One Time Pad

The image of the One Time Pad key is available to the public domain on Wikimedia Commons. It was provided by the United States Government and National Security Agency as a part of their official duties and therefore falls under the public domain.

Wikipedia Article on the One Time Pad


The article about the American Dyn DDoS attack was written by Nicky Woolf on October 26th, 2016 for The Guardian.

DDoS attack that disrupted internet was largest of its kind in history, experts say

Extra Links

CRYPTII, by @ffraenz

Cryptii is an open source web based project which allows you to convert between many different items, and it also contains some useful cryptography methods. It was instrumental in aiding the creation of this website, so it should get some credit.


W3schools is a collection of reference materials for HTML, CSS, and Bootstrap, along with other resources that went unused in the creation of this site. It was an immesurably important resource while building this website. Without it, this site would be a shadow of what it is now.

Tom Scott's YouTube Channel

Tom Scott has been an invaluable resource for understanding many of the cybersecurity vulnerabilities, and his videos have been consistently helpful, concise, and entertaining. Give him a look.