In the age of digital technology, every transaction or commitment should be bound by commercial contracts. However, a written contract may entail many drawbacks. To be specific, compiling commercial, economic contracts on a regular basis is timeconsuming, and a third party is needed to deal with or guarantee the terms of contracts. That will cost you a great deal of extra time, fee and procedure and require you to find a trustworthy third party to settle in case of conflict. If the third party cannot handle the incident, it will be handled by a regulatory authority. For those reasons, smart contracts come into effect. Smart contracts use computer code, giving AI the full control of terms and conditions among parties of the contracts.