These are the 2D representation of a 3D model that exists mainly to transpose image textures on to the model.
Blender offers tools for hand-painting textures with digital "brushes".
Blender allows us to tranpose geometric information to image texture format in a process called "baking".
Sometimes you need to use an external application to edit your textures. Here's how you can painless jump out of and back into Blender when texturing.
Test your knowledge to prove you know a thing or two about texturing with Blender.