Cryptocurrency is based on knowledge sharing on a distributed platform. The entire transactional history is for everyone to see. One blockchain is one thread of transaction. One unit or one block stores many transactions. The size of the block is 1MB and generally stores around 1000 to 2000 transactions. The data entered cannot be altered, nor can it be removed, enabling a system of complete transparency and trust. The entire money flow for the working model is beyond the traditional practices of controlling tax rates, credit usage, and money supply in the market.
There's a lot of ins and outs which can get confusing in arbitrage trading. We won't go into the technicals of why futures contracts trade at a premium to spot price. You can read a full explanation here. If it's not of interest to you, all you need to know is that there's a tendency, the further out in time the futures contract expires, for the premium to spot to be higher and higher in nominal percentage terms.