mtPaint is a painting program designed for creating icons and pixel-based artwork.
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Pixelitor is a free image editing software that supports layers, image effects, unlimited undo etc.
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Inkscape is an Open Source vector graphics editor, with capabilities similar to Illustrator, CorelDraw, or Xara X, using the W3C standard Scalable Vector Graphics (SVG) file format.
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Open Paint is an open source image editor for all major operating systems.
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GIMP is an acronym for GNU Image Manipulation Program.
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sK1 is an open-source illustration program that can substitute professional proprietary software like Corel Draw or Adobe Illustrator.
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