| Pigpen Cypher | Cipher |
| Symbol | Substitution Cipher |
| Cryptography | Encryption |
| Decryption | Algorithm |
| A method of encoding information so that it can only be accessed by authorized parties. | Also known as the Masonic Cipher, it is a substitution cipher used in cryptography that replaces letters with symbols and shapes. |
| A cipher that replaces each letter in the plaintext with a different letter, symbol, or number in the ciphertext. | A graphical representation used to represent something else, such as a letter or number in a cipher. |
| The process of converting plaintext into ciphertext using a cryptographic algorithm and a key. | The practice of securing communication from unauthorized access. |
| A sequence of steps or instructions used to solve a problem or perform a task. | The process of converting ciphertext back into plaintext using a cryptographic algorithm and a key. |
| Plaintext | Ciphertext |
| Key | Symbol Set |
| Repetition | Monoalphabetic Cipher |
| Polyalphabetic Cipher | Key Length |
| The encrypted message or data that is the result of an encryption process. | The original message or data that is to be encrypted. |
| The set of symbols used in a cipher to represent plaintext letters. | A secret value used to encrypt or decrypt information. |
| A substitution cipher in which each letter is replaced with a single, fixed symbol throughout the ciphertext. | The practice of using the same key repeatedly in a cipher. |
| The length of the key used in a cipher, typically measured in bits. | A substitution cipher in which the symbol used to replace a letter varies depending on its position in the plaintext. |
| Cryptanalysis | Caesar Cipher |
| Shift Value | Alphabet |
| Modulus Operator | Brute-Force Attack |
| Frequency Analysis | Vigenere Cipher |
| A type of substitution cipher in which each letter in the plaintext is shifted a certain number of places down the alphabet. | The process of analyzing encrypted information to decipher the original message or data. |
| A set of letters or symbols in a fixed order used to represent the basic sounds of a language. | The number of places by which each letter in the plaintext is shifted in the Caesar Cipher. |
| An attack on a cipher by trying every possible key until the correct one is found. | A mathematical operator used to perform division with remainder, often denoted by the percent symbol (%). |
| A polyalphabetic cipher that uses a keyword consisting of a repeating pattern of letters to encrypt a message. | The study of the frequency and distribution of letters or symbols in a text to help break a cipher. |
| Transposition Cipher | Rail Fence Cipher |
| Modulo Operator | Brute Force Attack |
| Kasiski Examination | Autokey Cipher |
| Playfair Cipher | Zigzag Pattern |
| A type of transposition cipher in which the plaintext is written diagonally on a criss-cross pattern. | A cipher that rearranges the letters or symbols of a message without changing them. |
| A cryptanalytic technique that involves trying every possible key until the correct one is found. This is usually only feasible for small key sizes. | A mathematical operation that finds the remainder when one integer is divided by another. The Vigenere Cipher uses this operator to perform its encryption and decryption operations. |
| "A polyalphabetic cipher similar to the Vigenere Cipher, but using the plaintext itself as part of the key sequence in order to overcome a weakness observed in the original Vigenere Cipher." | A cryptanalytic technique used to try and discover the length of the keyword used in a Vigenere Cipher by detecting repeating patterns in the ciphertext. |
| A pattern that moves in a back-and-forth motion like a zigzag | A polygraphic substitution cipher that uses a 5x5 table containing a keyword or phrase to encrypt pairs of plaintext letters. |
| Rows | Columns |
| Block Cipher | Secure Communication |
| Key Space | Brute Force |
| Known Plaintext | Dictionary Attack |
| The vertical lines of the zigzag pattern used to read off the ciphertext for the Rail Fence Cipher | The horizontal lines of the zigzag pattern used to write the plaintext for the Rail Fence Cipher |
| Communication that is encrypted and protected from unauthorized access | A cipher that encrypts a block of plaintext at a time and produces a corresponding block of ciphertext |
| A method used in cryptography to try all possible combinations until the correct one is found | The total number of possible keys that can be used by a cipher |
| A method of attempting to gain unauthorized access to a system by systematically attempting all possible combinations of words from a dictionary as passwords. | A type of attack where the cryptanalyst has access to both the plaintext and its corresponding ciphertext |
| Password Cracking | Rainbow Table |
| Password Strength | Two-Factor Authentication |
| Account Lockout | |
| A precomputed table used in password cracking to reverse cryptographic hash functions and quickly determine the original password. | The process of recovering passwords from data that has been stored or transmitted in an encrypted or hashed form. |
| A security mechanism that requires users to provide two different types of evidence before granting access to a system. | A measure of the effectiveness of a password in resisting unauthorized access. |
| A security feature that locks a user's account after a specified number of failed authentication attempts. | |