I don't know the difference. The difference can certainly be found on the internet. I can only contribute my experience as a user. The 980 is top! I would buy it again and again. It works perfectly. We use it every day. Because of our dog, there is always dog hair on the floor. During the dog walk (our dog doesn't love the 980) we have it vacuumed.
Works well. Goes well into corners and over carpets. Everything can be controlled from the app. Simply a relief in the household.