Books and academic papers
An Introduction to Mathematical Cryptography
Jeffrey Hoffstein, Jill Pipher and Joseph H. Silverman
This book focuses on public key cryptography and does not require any advanced mathematics as a prerequisite, making it an excellent introductory text for those new to cryptography.
Cryptography: Theory and Practice (Third Edition)
Douglas R. Stinson
This book provides a mathematically intensive examination of cryptography, which may be challenging for readers with little or no background in mathematics.
Cryptography Engineering: Design Principles and Practical Applications
Niels Ferguson, Bruce Schneier and Tadayoshi Kohno
This book focuses on the practical implementation of cryptography in real-world systems and discusses the decisions developers must make when applying cryptographic techniques.
The Codebreakers
David Kahn
A comprehensive history of cryptography and its profound impact on world events, from ancient times to the present day.
Handbook of Applied Cryptography
Alfred J. Menezes, Paul C. van Oorschot and Scott A. Vanstone
An excellent free online book that covers all the major areas of cryptography in detail.
A Graduate Course in Applied Cryptography
Dan Boneh and Victor Shoup
Another excellent free online book based on a graduate course in applied cryptography at Stanford University.
New Directions in Cryptography
Whitfield Diffie and Martin E. Hellman
This landmark paper by Whitfield Diffie and Martin Hellman marked the beginning of public key cryptography as we know it today.
Articles
- schneier.com
- The homepage of IT security and cryptography expert Bruce Schneier, where he blogs about security.
- grahamcluley.com
- The homepage of IT security expert Graham Cluley, where he blogs about security.
- schneier.com
- Bruce Schneier on why encryption is important for you and others.
- iacr.org
- The website of the International Association for Cryptologic Research, where news and papers from the academic world are published.
- wired.com
- An article about the tools Laura Poitras used to communicate securely with Edward Snowden and keep her work on the documentary Citizenfour safe.
- firstlook.org/theintercept
- An interesting article about how journalists and their sources use secure communication.
- spiegel.de
- The status of the NSA's work on breaking encryption (the article is in English).
- wired.com
- How a hacker, in just 30 minutes, hacked into a person's iCloud, Gmail, and Twitter accounts by exploiting companies' different security policies.
- grahamcluley.com
- How to hack into an email account just by knowing the victim's mobile phone number.
- wired.com
- How hackers remotely killed a Jeep Cherokee on the highway.
- wired.com
- How to disable a sniper rifle or change its target remotely.
- fusion.net
- A video illustrating how powerful social engineering can be.
- troyhunt.com
- Security expert Troy Hunt's list of security links.
- varonis.com
- The top 10 security people to follow on Twitter.
- ted.com
- Glenn Greenwald at TED in 2014 on why privacy matters.
- symantec.com
- Symantec's annual threat report, which provides an overview and analysis of the year's global threat activity.
Guides
- ssd.eff.org
- Tips, tools, and how-tos for safer online communication.
- privacytools.io
- Provides knowledge and tools to help protect your privacy against global mass surveillance.
- freedom.press
- A guide by Micah Lee on how to protect your privacy. Micah Lee helped, among others, Glenn Greenwald set up secure communication with Edward Snowden in 2013.
- firstlook.org
- A guide to creating a secure password using a method called "diceware".
- firstlook.org/theintercept
- Micah Lee explains how to chat securely and anonymously on Windows, Mac, and Android.
- theguardian.com
- A guide to staying secure by Bruce Schneier.
- freedom.press
- Why Flash is dangerous and how to manage it in your browser.
- medium.com
- A guide to tightening your security with VPNs, encryption, strong passwords, and more.
- lifehacker.com
- Why you should use a VPN provider and how to choose the best one for your needs.
- comparitech.com
- A review of the best VPN providers, rated for privacy and security.
- khanacademy.org
- Khan Academy's course on cryptography.
- coursera.org
- An online cryptography course from Stanford University.
- keylength.com
- Recommended key sizes for various cryptosystems such as RSA, ElGamal, AES, and hash functions.
Tools
- Tor Browser
- A browser that allows you to surf the web anonymously.
- HTTPS Everywhere
- Enhances your browsing security by encrypting your communications. Available as an extension for Firefox, Chrome, Opera, and Android.
- Ghostery
- Shows which websites are tracking you while you browse and allows you to block them. Available as an extension for Firefox, Chrome, Safari, and Opera.
- Disconnect
- Another service that shows and blocks tracking websites. Available as an extension for Firefox, Chrome, Safari, and Opera.
- uBlock
- uBlock is a content blocker for your browser that makes your web experience faster by blocking ads and other unwanted content. Available as an extension for Firefox, Chrome, and Safari.
- 1Password
- Software to manage your passwords, available for Mac, Windows, iOS, and Android.
- LastPass
- A free alternative password manager for Mac, Windows, Linux, iOS, Android, Windows Phone, and BlackBerry.
- F-Secure Freedome
- A VPN for Mac, Windows, iOS, Android, and Kindle Fire, including extra security features such as ad blocking.
- GPGTools
- PGP software for Mac, used to encrypt your emails.
- Gpg4win
- The Windows version of PGP software.
- GnuPG
- The Linux version of PGP software.
- pgp.mit.edu
- A public database of PGP keys hosted by MIT.
- Cryptocat
- A secure, browser-based chat program available for Chrome, Firefox, Safari, Opera, iOS, and OS X.
- Bleep
- A private chat app for iOS, Android, Mac, and Windows, where received messages self-destruct after a short time, similar to Snapchat.
- Adium
- A chat client for Mac that encrypts your communication using OTR (Off The Record).
- Pidgin
- A Windows chat client where the OTR extension can be downloaded from the same website.
- Tor Messenger
- An OTR (Off The Record) chat client for Windows, Mac, and Linux, developed by the Tor Project.
- Open Whisper Systems
- Open Whisper Systems created an app for iOS and Android called Signal, which lets you communicate securely (even Edward Snowden uses Signal).
- Ricochet
- An anonymous and secure chat program that uses the Tor network.
- ProtonMail
- A secure email service with end-to-end encryption.
- OnionShare
- Securely and anonymously share files of any size.
- miniLock
- A Chrome extension that can be used to send encrypted files to other miniLock users.
- SecureDrop
- A service that lets people anonymously send you documents and messages.
- Boxcryptor
- Encrypt your files and folders stored in Dropbox and other cloud services.
- Tails
- A live operating system that protects your privacy and keeps you anonymous.
- haveibeenpwned.com
- Check if any of your accounts have been compromised in a data breach.