GIMP is an acronym for GNU Image Manipulation Program. It works on many operating systems, in many languages and is a powerful program for photo retouching, image composition and image authoring.

Blender is a full functional integrated 3D creation software suite for 3D modeling, animation, rendering, post-production, interactive creation and playback. It lets users create high quality 3D graphics, movies and replay real-time, interactive 3D content.

Inkscape is an Open Source vector graphics editor using the W3C standard Scalable Vector Graphics (SVG) file format. Supported SVG features include shapes, paths, text, markers, clones, alpha blending, transforms, gradients, patterns, and grouping.

IrfanView is a very fast, small, compact and innovative freeware (for non-commercial use) graphic viewer for Windows. It is trying to be simple for beginners and powerful for professionals. IrfanView supports many file formats and is one of the few programs capable of lossless JPG rotation.