Paint.Net is a free opensource Photo Editing Software which was originally funded by Microsoft and was looked at as a replacement for the simple MS Paint software available in all versions of Windows operating system. Paint.Net has evolved from there on into a serious competitor to commercial software like Adobe PhotoShop and popular opensource software like GIMP. It has almost all the rich features on most of the popular image editing software.
It features an intuitive and innovative user interface with support for layers, unlimited undo, special effects, and a wide variety of useful and powerful tools. An active and growing online community provides friendly help, tutorials, and plugins.
One of the stand out features that I like in Paint.Net is the history which allows you to go back to any number of steps and redo. This gives you a complete control of what changes you made and where you made a mistake. It also sports the features like special effects, gradient tool, layers etc.
More important for being an opensource software is that you need an active community and Paint.Net has great community that backs the development process.
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