im just hear bitcoin price insurance, what is that
You should read up on option strategies, but basically, say you own 100 shares of XYZ. XYZ currently trades at $100/share. You want protect yourself against a downturn, so you decide to buy a $95 put contract. That contract gives you (buyer) the right to sell 100 shares (1 option contract per 100 shares) of XYZ at $95 (Strike price) at any point between now and an agreed upon point in the future (expiration date).
The seller has the obligation of taking those shares if you exercise. This is risky, as XYZ could plummet to, say, $50 and now the seller has to buy at $95 and sell at $50. This risk is reflected in the price of the contract.
If XYZ rises, you profit from your shares, but lose the cost of the put contract. If it falls, you get to sell at $95, even if XYZ goes bankrupt.
That's put insurance in a nutshell. There's also calls which give the buyer the right to buy at a certain price. In November 2013 if you could have purchased a $2000 BTC call, it probably would have been extremely pricey, but in early 2014 when the price plummeted you would have only been out the cost of the call contract, instead of holding onto a depreciating asset.