Can one put a transparent image over a background picture without using nodes. I have a cartoon with transparent back and I want to put it over an image.
Any image editor (GIMP, Photoshop, Krita, etc) that can handle layers can do that as well, but to do it in Blender, you have to use the compositing nodes. Specifically, you would use an Alpha Over node. to combine the two images with the transparent image in the bottom slot and the background image connected to the top slot. (Incidentally, you can also put the transparent image over a color with the same node by plugging in an RGB input rather than a second image node.)