A photo editor is a bit straightforward. I would edit photos or digital artwork in the way requested by you. Some examples of this would be altering the hue, connecting photos into a gif, darkening the image, or merging two or more photos together.
My background as a photo editor is a bit more recent. While I took a couple courses in high school, I didn't really start dabbling in it seriously until the beginning of this year. I have done a quite a few edits to screenshots that my gaming community, as well as a few others, have submitted.