3DES – Symmetric-key block cipher (or Triple Data Encryption Algorithm (TDEA or Triple DEA), which applies the Data Encryption Standard (DES) cipher algorithm three times to each data block.
AES – Symmetric-key block cipher algorithm and U.S. government standard for secure and classified data encryption and decryption (also known as Rijndael).
Blowfish – Symmetric-key block cipher, designed in 1993 by Bruce Schneier. Notable features of the design include key-dependent S-boxes and a highly complex key schedule.
RSA – One of the first practical public-key cryptosystems and is widely used for secure data transmission. In RSA, this asymmetry is based on the practical difficulty of factoring the product of two large prime numbers, the factoring problem.
Transform Encryption (aka Proxy Re-Encryption) – Transform encryption uses three mathematically related keys: one to encrypt plaintext to a recipient, a second to decrypt the ciphertext, and a third to transform ciphertext encrypted to one recipient so it can be decrypted by a different recipient.
MD5 – Widely used hash function producing a 128-bit hash value. MD5 was initially designed to be used as a cryptographic hash function, but it has been found to suffer from extensive vulnerabilities. It can still be used as a checksum to verify data integrity, but only against unintentional corruption.
SHA1 – Cryptographic hash function designed by the NSA. SHA-1 produces a 160-bit hash value known as a message digest. SHA-1 is no longer considered secure against well-funded opponents.
SHA2 – Set of hash functions designed by the NSA. SHA-256 and SHA-512 are novel hash functions computed with 32-bit and 64-bit words, respectively. They use different shift amounts and additive constants, but their structures are otherwise virtually identical, differing only in the number of rounds.
Practical Cryptography for Developers – Developer-friendly book on modern cryptography (hashes, MAC codes, symmetric and asymmetric ciphers, key exchange, elliptic curves, digital signatures) with lots of code examples.
Security Engineering – There is an extraordinary textbook written by Ross Anderson, professor of computer security at University of Cambridge.
The Cryptoparty Handbook – This book provides a comprehensive guide to the various topics of the computer and internet security.
Understanding Cryptography – Often overlooked, this book is a boon for beginners to the field. It contains plenty of exercises at the end of each chapter, aimed at reinforcing concepts and cementing ideas.
A Self-Study Course In Block-Cipher Cryptanalysis -This paper attempts to organize the existing literature of block-cipher cryptanalysis in a way that students can use to learn cryptanalytic techniques and ways to break algorithms, by Bruce Schneier.
Applied Cryptography – Cryptography is present in everyday life, from paying with a credit card to using the telephone. Learn all about making and breaking puzzles in computing.
Crypto Strikes Back! – This talk will cover crypto vulnerabilities in widely-deployed systems and how the smallest oversight resulted in catastrophe.
Cryptography – A practical oriented course in Cryptography by University of Maryland College Park.
Cryptography – Stanford University – This course explains the inner workings of cryptographic primitives and how to correctly use them. Students will learn how to reason about the security of cryptographic constructions and how to apply this knowledge to real-world applications.
Cryptography I – The course begins with a detailed discussion of how two parties who have a shared secret key can communicate securely when a powerful adversary eavesdrops and tampers with traffic. We will examine many deployed protocols and analyze mistakes in existing systems.
Cybrary Cryptography – This online course we will cover how cryptography is the cornerstone of security, and how through its use of different encryption methods, such as ciphers, and public or private keys, you can protect private or sensitive information from unauthorized access.
Theory and Practice of Cryptography – Introduction to Modern Cryptography, Using Cryptography in Practice and at Google, Proofs of Security and Security Definitions and A Special Topic in Cryptography.
blackbox – safely store secrets in Git/Mercurial/Subversion.
certbot – Previously the Let’s Encrypt Client, is EFF’s tool to obtain certs from Let’s Encrypt, and (optionally) auto-enable HTTPS on your server. It can also act as a client for any other CA that uses the ACME protocol.
Coherence – Cryptographic server for modern web apps.
cryptomator – Multi-platform transparent client-side encryption of your files in the cloud.
gpg – Complete and free implementation of the OpenPGP standard. It allows to encrypt and sign your data and communication, features a versatile key management system. GnuPG is a command line tool with features for easy integration with other applications.
ironssh – End-to-end encrypt transferred files using sftp/scp and selectively share with others. Automatic key management works with any SSH server. Encrypted files are gpg compatible.
Nipe – Nipe is a script to make Tor Network your default gateway.
sops – sops is an editor of encrypted files that supports YAML, JSON and BINARY formats and encrypts with AWS KMS, GCP KMS, Azure Key Vault and PGP.
ves – End-to-end encrypted sharing via cloud repository, secure recovery through a viral network of friends in case of key loss.
PolarSSL – PolarSSL makes it trivially easy for developers to include cryptographic and SSL/TLS capabilities in their (embedded) products, facilitating this functionality with a minimal coding footprint.
themis – High level crypto library for storing data (AES), secure messaging (ECC + ECDSA / RSA + PSS + PKCS#7) and session-oriented, forward secrecy data exchange (ECDH key agreement, ECC & AES encryption). Ported on many languages and platforms, suitable for client-server infastructures.
SwiftThemis – Swift wrapper on Themis for iOS and MacOS. High level crypto library for storing data (AES), secure messaging (ECC + ECDSA / RSA + PSS + PKCS#7) and session-oriented, forward secrecy data exchange (ECDH key agreement, ECC & AES encryption).
Root Labs rdist – Nate Lawson and his co-authors write on a variety of topics including hardware implementation, cryptographic timing attacks, DRM, and the Commodore 64.
Salty Hash – Covers topics on encryption, data control, privacy, and security.
Schneier on security – One of the oldest and most famous security blogs. Bruce covers topics from block cipher cryptanalysis to airport security.
metzdowd.com – “Cryptography” is a low-noise moderated mailing list devoted to cryptographic technology and its political impact.
Modern Crypto – Forums for discussing modern cryptographic practice.
randombit.net – List for general discussion of cryptography, particularly the technical aspects.
Cryptolab – is a set of cryptography related tools.
CrypTool – Great variety of ciphers, encryption methods and analysis tools are introduced, often together with illustrated examples.
CyberChef – a web app for encryption, encoding, compression, and data analysis.
keybase.io – Keybase maps your identity to your public keys, and vice versa.
Cryptography Stackexchange – Cryptography Stack Exchange is a question and answer site for software developers, mathematicians and others interested in cryptography.
Cryptopals Crypto Challenges – A series of applied cryptography challenges, starting from very basic challenges, such as hex to base 64 challanges, and gradually increasing the difficulty up to abstract algebra.
IACR – The International Association for Cryptologic Research is a non-profit scientific organization whose purpose is to further research in cryptology and related fields.
Learn Cryptography – Dedicated to helping people understand how and why the cryptographic systems they use everyday without realizing work to secure and protect their privacy.
Subreddit of Cryptography – This subreddit is intended for links and discussions surrounding the theory and practice of strong cryptography.