Cipher Tools

Let's say that you need to send your friend a message, but you don't want another person to know what it is. You can use a full-blown encryption tool, such as PGP. If the message isn't that important or if it is intended to be decrypted by hand, you should use a simpler tool. This is a page dedicated to simple text manipulation tools, which all can be replicated with just paper and pencil. If you know of another cipher that you think should be on here, leave me a message below.

Cryptography When I wrote my first book, Fermat’s Last Theorem, I made a passing reference to the mathematics of cryptography. Although I did not know it at the time, this was the start of a major interest in the history and science of codes and code breaking, which has resulted in a 400-page book on the subject, an adaptation of the book for teenagers, a 5-part TV series, numerous talks and lectures, the purchase of an Enigma cipher machine and the development of an interactive crypto CD-ROM. In the Crypto Corner, you will find details about my book on cryptography (The Code Book), information about my TV series based on the book (The Science of Secrecy) and you can explore the Black Chamber, which is an interactive encryption and codebreaking section. You will also find a section about the Cipher Challenge, there are some cryptograms (coded messages) for you to try and crack, a free downloadable CD-ROM version of The Code Book, and a quick Q&A based on the questions I am most often asked.

Sharky's Vigenere Cipher This page is for amusement only. Instructions are given below this form. instructions: Enter the string to encrypt or decrypt in the Input field (you may copy and paste it from another text editor). Enter the key in the Key field. Sudoko Solver in Excel Solve Sudoku with Excel We are a little slow here in the midwest. The Akron Beacon Journal just recently started publishing a daily Sudoku puzzle in our comic strip pages. Wow! Talk about a time waster! I nearly became addicted to solving these puzzles. Convert hexadecimal to text Convert text into hexadecimal format. Computers store text as numbers, and with hex you display the numbers not as a decimal number, but in base 16. Hex or base 16 or hexadecimal is a numeral system that uses 16 symbols. The symbols include 0-9 and a-f (sometimes A-F). An example of a hexadecimal number is 3BF2. Computer science applications can use hexadecimal for binary coding in computing and digital electronics.

Online Shakespeare Course: Shakespeare After All with Harvard Faculty Marjorie Garber, PhD, William R. Kenan Jr. Professor of English and American Literature and Language and of Visual and Environmental Studies, Harvard University This free online Shakespeare course focuses on Shakespeare’s later plays beginning with Measure for Measure and ending with The Tempest.

Playfair Cipher The Playfair cipher encrypts pairs of letters (digraphs), instead of single letters. This is significantly harder to break since the frequency analysis used for simple substitution ciphers is considerably more difficult. Memorization of the keyword and 4 simple rules is all that is required to create the 5 by 5 table and use the cipher. The Playfair cipher uses a 5 by 5 table containing a key word or phrase. Polyalphabetic Substitution Ciphers Introduction The monoalphabetic (simple) substitution cipher uses only one replacement scheme for all letters of the plain text. Polyalphabetic ciphers use more than one replacement scheme. The Vigenere Cipher Given a letter of the plain text and one letter of the key word, the following table is used for encryption: The letter of the key word is located in the first row and the plain text letter is located in the first column.