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What are smart contracts, how do they work and why are they necessary?


A smart contract is a digital contract in the form of computer code that establishes an algorithm for specific actions and governs certain conditions that must be met by the parties entering into the agreement. If the conditions established by the smart contract are observed, a sequence of actions is automatically launched according to the “if…then” principle.

Smart contracts allow complete strangers from different parts of the world to conduct safe and fast transactions without involving intermediaries or worrying about outcomes, given that the fulfilment of all the obligations of the parties is monitored by mathematical algorithms. Transactions based on smart contracts are fully automated: the smart contract is integrated into a blockchain’s code, and the algorithm is executed independently if all the conditions of the contract are met.

Why smart contracts are important

Smart contracts are mostly used to ensure the operation of decentralized applications, acting as a guarantee of the parties’ compliance with all agreements. Smart contracts are also used in transactions involving cryptocurrencies and NFTs.

Because activities on the blockchain are almost completely unregulated by government institutions and other state bodies, smart contracts ensure compliance with the terms of transactions and guarantee their security.

Smart contracts: A brief history

The of automating transactions itself isn’t new. American computer scientist and cryptographer Nick Szabo came up with the concept back in 1994. He put forward the idea of developing a protocol that would execute transactions automatically and monitor the fulfilment of their obligations by the parties. At that time, however, the technological expertise was not yet sufficiently developed to implement his idea. The scientist’s concept only became fully operational in 2013 using Ethereum as its basis, when a special protocol was created allowing smart contracts to function fully.

How smart contracts work and what makes them different from standard agreements

Smart contracts are inextricably tied to the blockchain, constituting part of its code. They fulfil the function of the “paper” contracts we’re used to, only in digital form. This means that the conditions are put in place using mathematical algorithms and programming languages, and the parties sign these agreements with an electronic signature rather than physically.

All the conditions provided for by the smart contract are binding, and the transaction is considered complete only after the parties have fulfilled all of their obligations in full and the participants have achieved the desired result. This could mean topping up a digital wallet with crypto, exchanging one token for another on a DEX, and more.

All smart contracts contain:

  1. Monitor compliance with the conditions they stipulate.
  2. Based on the results of this process, make a decision:
    • to execute the transaction if the parties have met all conditions;
    • impose fines and penalties or potentially even block access to assets if the conditions have not been met.

The activation of a smart contract and the execution of its programmed actions begins with a transaction initiated by a user via their crypto wallet, or a message from another smart contract.

How does a smart contract differ from a standard agreement?

The following key differences can be identified:

  • all transactions are carried out automatically on the blockchain;
  • smart contracts are based on computer code;
  • changes cannot be made to contracts after they have been signed;
  • information about the parties to the deal is stored on the blockchain;
  • no intermediaries are involved in the transactions.

Use cases for smart contracts

Smart contracts are used in a number of fields. They can help automate many business processes, eliminate the need for intermediaries in transactions, and reduce expenditure on human labour.

Smart contracts are most often used on cryptocurrency and NFT markets, and in the metaverse. They can, however, also be used in more traditional fields.


There are many different kinds of operations involved in the issuance and repayment of loans. The use of blockchain technology and smart contracts makes it possible to formalize all algorithms used in a network’s code and ensure that they cannot be changed. This can greatly simplify security systems, help to detect cases of fraud, automate the issuance of loans and more.

Additionally, using smart contracts in lending makes it possible to optimize efforts to control the movement of assets, and monitor the status of assets pledged when applying for mortgages.


The use of smart contracts is also beneficial in insurance. The protocol adopted looks as follows:

  • the parties enter into a smart contract, which specifies the terms of the insurance policy;
  • an oracle keeps track of the insurable event;
  • when the event is confirmed, the algorithm is executed;
  • If all conditions are met, the smart contract guarantees the receipt of the insured amount. 

An oracle is a data provider that, when it receives a request from a smart contract, provides reliable information received from sources outside the network that is required in order for the programmed protocol to take place.


With the emergence of non-fungible tokens (NFTs), many artists, musicians, photographers and other creators have begun using the blockchain to host and sell their creations. NFTs also require copyright protection, however, and this is where smart contracts come to the rescue. They stipulate all the terms of the transaction between the purchaser and creator.

Business reputation management

Smart contracts can greatly help agencies compiling independent and fair ratings (of companies, people, products etc.) They ensure that all evaluations of a given topic cannot be changed, meaning that negative reviews will be impossible to edit or delete, and users will be able to see the real state of affairs.

Supply chains

Logistics always involves a very large amount of data about shipments, freight routes, suppliers, customers and more. If all this information is streamlined using the blockchain, it will be much simpler to process, which in turn will help to significantly reduce human error along the supply chain.
Smart contracts can also be used to positive effect in healthcare, the electoral process, gambling, property rentals and much more.


Smart contracts represent a promising new technology that makes it possible to automate and carry out transactions in complete transparency, not just on the cryptocurrency market, but also in many areas of the “real economy”. Their key function is to simplify and optimize business processes.

Smart contracts have of course revolutionized blockchain technology. Over time, smart contracts and the blockchain have the potential to significantly impact many areas of people’s lives.