The blockchain technology is next big paradigm.With its security,blockchain can assure instantenous crypted transactions.We talk now about decentralized systems that aim to make everyone contribute to the blockchain network. Notice: you don't have to understand blockchain in order to read this article This article has no purpose to explain blockchain mechanism. Smart contract are programmed to execute instructions when the conditions are met. For example Alice gives 5 BTC to Bob to purshase a bicycle .Bob receives the 5 BTC but how can we assure that Bob gives the Bicycle to Alice .Simple as that when the transaction Alice to Bob is executed 5 BTC will go from Alice to Bob and if Bob don't give the Bicycle to Alice the smart contract will be autcomatically executed and the 5 BTC will go back to Alice. So smart contract assure the transaction and avoid stealing properties. "Code is the law" the next subject is an idea how to make a financial equilibriu...