It has always been essential for every version of CrypTool to come with thorough documentation about its features. Whenever the user presses F1 on their keyboard, corresponding information about the feature currently selected appears.
You can directly visit one of the CrypTool topic pages by clicking one of the five buttons here below.
The CrypTool project in general
CrypTool 1 (C++)
CrypTool 2 (C#, .NET, WPF)
JCrypTool (Java, Eclipse, RCP)