Documize - Enterprise-grade wiki and knowledge management platform
ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
Boardist - Personal workspace for all the data
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
ReadTheDocs - Spend your time on writing high quality documentation, not on the tools to make your documentation work.
LightShot - The fastest way to take a customizable screenshot.