Gimp

https://www.gimp.org/tutorials/

File formats : https://www.gimp.org/tutorials/ImageFormats/

Raster vs Vector https://www.artworkabode.com/article/inkscape-vs-gimp https://docs.gimp.org/2.10/en/gimp-using-paths-and-svg.html

Gimp Components https://docs.gimp.org/2.10/en/gimp-colors-components-menu.html

https://www.gimp.org/tutorials/Basic_Color_Curves/

Transparency https://itsfoss.com/remove-image-background-gimp/ https://www.gimp.org/tutorials/Layer_Masks/

Antialiasing https://docs.gimp.org/2.8/en/plug-in-antialias.html https://www.gimp.org/tutorials/Anti-Aliased_Threshold/

Fonts and Text https://www.gimp.org/unix/fonts.html https://docs.gimp.org/2.6/en/gimp-tool-text.html

https://docs.gimp.org/2.6/en/gimp-concepts-text.html

Layers

https://docs.gimp.org/en/gimp-image-combining.html https://www.gimp.org/tutorials/Layer_Masks/ https://docs.gimp.org/en/gimp-layer-groups.html

Selections

https://docs.gimp.org/en/gimp-tools-selection.html https://docs.gimp.org/en/gimp-using-selections.html

Cropping

https://www.gimp.org/tutorials/GIMP_Quickies/ https://docs.gimp.org/en/gimp-tutorial-quickie-crop.html

Gimp ( Continued )

Blurs and shadows

https://docs.gimp.org/2.10/en/gimp-filter-drop-shadow.html

https://docs.gimp.org/2.10/en/script-fu-fuzzy-border.html

https://www.wikihow.com/Use-Drop-Shadow-in-GIMP

Objects and Paths

https://docs.gimp.org/2.10/en/gimp-using-paths.html

https://www.gimp.org/tutorials/Drawing_Shapes/

https://www.gimp.org/tutorials/Bezier_Selections/

Alignment

https://docs.gimp.org/en/gimp-tool-align.html

https://docs.gimp.org/2.10/en/plug-in-align-layers.html

Screen shots

https://www.gimp.org/screenshots/

https://docs.gimp.org/2.10/en/gimp-file-create.html

http://gimpchat.com/viewtopic.php?f=23&t=7695