A smart contract is a self-executing contract with the terms of the agreement between buyer and seller being directly written into lines of code. The code and the agreements contained therein exist across a distributed, decentralized blockchain network. ApplicationsIn 1998, Szabo proposed that smart contract infrastructure can be implemented by replicated asset registries and contract execution using cryptographic hash chains and Byzantine fault-tolerant replication.[44] Askemos implemented this approach in 2002 using Scheme later adding SQLite as contract script languageOne proposal for using bitcoin for replicated asset registration and contract execution is called “colored coins”. Replicated titles for potentially arbitrary forms of property, along with replicated contract execution, are implemented in different projects. As of 2015, UBS was experimenting with “smart bonds” that use the bitcoin blockchain in which payment streams could hypothetically be fully automated, creating a self-paying instrument. Inheritance wishes could hypothetically be implemented automatically upon registration of a death certificate by means of smart contracts.[53][54] Birth certificates can also work together with smart contracts. Smart contracts can also be used to handle real estate transactions (i.e. via Propy, .)and blockchain solutions are also proliferating on the field of title records and in the public register. Smart contracts can also be used in employment contracts, especially temporary employment contracts, offering benefits for both employer and employee.[
