## Cryptography Challenge

Cryptography, or cryptology is the practice and study of techniques for secure communication. Cryptography relies on using more or less complex encryption algorithms to encode a readable message (plaintext) into a collection of characters (ciphertext) that is hard to decipher

## Perseverance’s Parachute Secret Message Encoder

On February 18, 2020, NASA successfully landed its rover “Perseverance” on planet Mars. To slow down its descent the rover deployed a parachute. The whole operation was filmed and relayed on the Internet. You can watch the official NASA video

## XOR Encryption Algorithm

The XOR Encryption algorithm is a very effective yet easy to implement method of symmetric encryption. Due to its effectiveness and simplicity, the XOR Encryption is an extremely common component used in more complex encryption algorithms used nowadays. The XOR

## Visual Cryptography

Visual cryptography is a technique that consists of hiding information (text/symbols/graphics) within two semi-transparent pictures (called layers). Overlaying both pictures exactly on top of one another, will reveal the hidden information. Using this technique, it is impossible to retrieve any

## Atbash Cipher Algorithm

The Atbash Cipher is a monoalphabetic substitution cipher that was originally used for the Hebrew alphabet. It is one of the earliest known subtitution ciphers to have been used. As opposed to a Caesar Cipher, the Atbash cipher does not

## MRX20 – Mission to Mars

The MRX20 probe was sent to Mars by the Inter-Continental Space Agency (ICSA) a few years ago. It was due to return to planet Earth just a few days ago. The probe collected a large amount of samples from the

## Caesar Shift Decoder

A Caesar Shift cipher is a type of mono-alphabetic substitution cipher where each letter of the plain text is shifted a fixed number of places down the alphabet. For example, with a shift of 1, letter A would be replaced

## Secret Santa’s Ciphers

It’s only few days before Christmas so here are some secret messages from Santa for you to decode… Secret Message #1, encoded using Maritime Signal Flags International maritime signal flags are various flags used to communicate with ships. Each flag

## Vatsyayana cipher

The Vatsyayana cipher is a simple substitution cipher where the 26 letters of the alphabet are organised into 13 pairs of characters. These pairs are then used to encrypt the text by direct substitution of the letters in the pairs.

## Caesar Shift (Substitution Cipher)

A Caesar Shift cipher is a type of mono-alphabetic substitution cipher where each letter of the plain text is shifted a fixed number of places down the alphabet. For example, with a shift of 1, letter A would be replaced