Image and photo manipulation software designed to be used on computers that run Windows.

Speedy Painter is an OpenGL based painting software for Windows. It supports Wacom digitizers to vary size and opacity of brush strokes according to pen pressure.

Krita is a free sketching and painting program. It was created with the following types of art in mind:

MyPaint is a fast and easy open-source graphics application for digital painters. It lets you focus on the art instead of the program. You work on your canvas with minimum distractions, bringing up the interface only when you need it.