Paint.NET
Paint.NET is free image and photo editing software for PCs that run Windows.
GIMP
GIMP provides the tools needed for high quality image manipulation. From retouching to restoring to creative composites, the only limit is your imagination.
KRITA
Krita is a professional FREE and open source painting program. It is made by artists that want to see affordable art tools for everyone.
Tux Paint
Tux Paint is a free, award-winning drawing program for children ages 3 to 12 (for example, key stages 1 and 2). Tux Paint is used in schools around the world as a computer literacy drawing activity.
XnView MP
XnView MP is the enhanced version of XnView Classic. It is a powerful cross-platform media browser, viewer and converter. Compatible with more than 500 formats.
Greenshot
Greenshot is a light-weight screenshot software tool for Windows
ShareX
ShareX is a free and open-source screenshotting and screencasting program for Microsoft Windows targeted towards power users, developers and testers.