What actually is a smart contract?

Von | 4. Januar 2021

Smart contracts are an essential cornerstone of decentralized finance (DeFi). But how do smart contracts actually work?

The article is taken from the BTC-ECHO Academy . There you will find exciting background information as well as interesting introductory courses on Bitcoin, Blockchain and Co.

A smart contract is an algorithm that ensures the decentralized execution of „contracts“. A conventional contract apart from blockchain technologies consists of an agreement that is made between several people. As a rule, the contract ensures that both parties can insist on their claims and, in the event of a dispute, can present the contract as evidence to justify certain claims and rights. A classic contract is the rental contract, which, to put it simply, consists of two elements:

The tenant transfers the rent to the landlord

The landlord leaves the apartment to the tenant

Contracts often consist of sequences in “if-then” form. When the tenant pays his rent (for the first time), he receives the key for the apartment. This process can be simplified with smart contracts, as the sequence can be automated.

Smart contract applications

A smart contract says nothing else than a sequence of activities that are carried out when a certain event occurs. This can range from a rental agreement to complex financial transactions. What is the difference between smart contracts and traditional contracts?

Eliminate third parties It is

crucial that smart contracts generally do not involve third parties. A notary is not necessary to conclude a smart contract, as would be the case, for example, with property transfers with conventional contracts. Instead, the smart contract is executed by the nodes in the network.

Activities are carried out automatically

The if-then structures ensure that the following activity is carried out as soon as the event occurs. If person A and person B conclude a smart contract and A fulfills his condition, then the necessary action that follows is automatically carried out in the network. It is not necessary that B has to be actively or a third party informed at this point in time. Instead, the nodes can check the status themselves at any time.

All participants are informed of status changes.

The decentralized structure requires that the individual nodes process consistent information. This means that all nodes know about status changes when an event occurs.
How is a smart contract executed?

There are different types of smart contracts. The best-known platform is Ethereum. There, smart contracts themselves are treated like an account that acts autonomously. So there are no single individuals who have access to this account. Instead, the actions to be carried out are carried out in the network. In simplified terms, this account can be thought of as a set of instructions (program code) that are executed. This includes performing calculations, storing information, and sending transactions to other accounts.

Although the smart contracts are written by people and stored on the blockchain, execution is then solely the responsibility of the network and the user no longer has the opportunity to make changes. This means that errors can still occur due to incorrect programming.