Here is "Boxmining" from youtube explaining Plasma and Lightning Networks.
I do have issues myself with this. Every coin in the blockchain has its history and authentication embedded into its coding. If the coin leaves the block chain how will those transactions be traced or authenticated? Could this lead to fraud, or is it as simple as 1 coin leaves and 1 coin returns no harm no foul? Maybe those transactions are compressed.
Anyway, it is only in the proposal stage at the moment. They believe it is possible and will lead to the future of cryptocurrency. I am sure miners will love this. But people who find store value in the limited number of bitcoin, for example, will not. Leads me to believe not every cryptocurrency will adopt this tech, well not in whole maybe in part for the speed upgrade.
Let me know what your thoughts are on this issue. It is an exciting time here in the cryptocurrency world.