Image editing

• Picasa - Free image viewer and editor from Google. Imports and categorizes images in your computer, if you choose to do so. Gives you choice to publish or to not publish photos to your web album. Supports .webp format of Google, one of the few softwares that do.

• GIMP - GNU Image Manipulation Program. Free and Open Source. Can be used for creating original artwork. Have a host of readily available plugins. Perhaps most well known free image software out there.

• Realworld Paint - Portable image editor. Draw pictures, edit photos, create animated GIFs. Works on Windows. Supports .webp format apart from other file formats.

• Photoscape - Fun and easy to use. Comes with viewer, editor, batch editor, raw converter, color picker and much more. 

• Serif PhotoPlus - Imports photo from your computer. Simple tools, easy to use. 100% free as it says on the website.