VeraCrypt - VeraCrypt is a free open source disk encryption software for Windows, Mac OSX and Linux.
ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
Axcrypt - AxCrypt - Password Protect Files With Strong Encryption. AxCrypt is the leading open source file encryption software for Windows.
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Windows BitLocker - This topic provides a high-level overview of BitLocker, including a list of system requirements, practical applications, and deprecated features.
LightShot - The fastest way to take a customizable screenshot.