What is "cryptool"

CrypTool is an open source e-learning tool illustrating cryptographic and cryptanalytic concepts.

CrypTool implements more than 300 algorithms. Users can adjust these with own parameters. The graphical interface, online documentation, analytic tools and algorithms of CrypTool introduce users to the field of cryptography. Classical ciphers are available alongside asymmetric cryptography including RSA, elliptic curve cryptography, digital signatures, homomorphic encryption, and Diffie–Hellman key exchange, many of which are visualized by animations.

CrypTool also contains some didactical games, and an animated tutorial about primes and elementary number theory.