Think of those moving Harry Potter photos… It’s also a new word, so you’re super-excused for not knowing it! It simply means a “looping” photograph. You begin with a SINGLE image (not a movie file), like a JPG, and then you use Plotagraph to “animate” it. The resulting image is a repeating movie file that loops so smoothly, you can’t tell the seam. There’s also some crazy new tech on there, like morphing and more.
See some examples and how it is done at https://www.stuckincustoms.com/plotagraph-review/