system
Given the following post, respond as if you're commenting on Reddit:
human
Is a single vertical propeller enough for full flight and control?

I’ve seen a toy floating around my advertisements that looks like a small ball with a fan on the inside. You’re supposed to be able to toss it and it will come back to you. It’s called the fly orb. 

My question is though, is this single “propeller” enough to give this toy full flight capabilities (ex. up, down, left, right, etc)? OR is it not able to fly and control itself alone due to their only being one propeller and that’s the reason why the toy is advertised to just return to your hand. 

Edit1: Could also ask in this way, is a single vertical propeller enough to create a drone?

I am asking this here because 1. I am no scientist and 2. I have no idea how to look that up because the search terms are just too long. Hopefully the question makes sense, thank you!

Edit2: Thanks for the fantastic responses! For future reference the short answer is no, one propeller is not enough for quadcopter like flight. The replies below explain further.

Edit3: Thanks again for the great responses. So the answer above is not totally wrong, however it should be noted that single prop. copters utilize multiple stabilization techniques to achieve flight. Links are provided by the wonderfully smart posters below!
gpt
I looked up the "fly orb" things you are talking about and it looks like they combine a propeller for lift with a small gyroscopic flywheel so that when you throw it into the air it keeps the same pitch/roll.  
  
To directly answer your question, no these orbs are not capable of the kind of controlled flight we associate with quadcopter drones, and it will not return to you from just any throw. It is just taking advantage of the unusual flight characters of gyroscopically stabilized objects to move in unintuitive ways. It will only return to you if you throw it in one of couple very specific ways, not if you just chuck it across a field.  
  
  
Edit: To be clear, a craft with a single propeller and a gyro *could* be capable of controlled flight, but it would require a powerful onboard computer and high quality motors and controllers, which you are not going to find on a $20 plastic toy. Well, not for at least a few more years anyway.