A bubble is when some market manipulators drive the price above its value. Like what we are seeing in bitcoin price movement right now. Beginning this year, we are just below the $1000 price and now we have touched $6000 and the price is tagged at $5700 currently.

However, I think we are already pass the bitcoin bubble of 2013, wherein there's a lot of factors that contributed to the market crash. 2017 is a new where we see new investors entering the market, and its hard to manipulate the price because there's really a lot of investors right now. Gonna be hard for whales to try and get the price to go lower and buy in dips unlike before.