Smart contracts are computer programs that automatically execute the terms of the contract when certain events occur. They reside on the blockchain and operate without intermediaries, ensuring transparency, predictability, and immutability of results. The idea is based on the "code as law" principle: the rules for executing the contract are written in code and executed automatically by network nodes. Key Characteristics of Smart Contracts
Autonomy: Once deployed, the contract begins to execute on its own, without trusting a specific person or organization.
Code Integrity: The rules and conditions of the contract are encoded in the contract and are accessible to any network participant.
Immutability: Code modifications after deployment are possible only through specially designed mechanisms (e.g., proxy architectures) or with the consent of the parties.
How They Work
Development and Deployment: Programmers write a contract on the chosen blockchain platform and deploy it to the network. The contract receives its own unique address space.
State Storage: The contract stores data (counter values, balances, access permissions, etc.) in the blockchain state.
Transaction Interaction: Users invoke contract functions through transactions, paying a "gas" or execution fee.
Execution and Consensus: Network nodes execute the contract code in response to transactions and reach a consensus state, ensuring determinism and transparency.
Transparency: The contract code and state are accessible to all participants.
Security through Cryptography: Access to funds and data is controlled using cryptographic methods.
Trustless: Participants do not need to trust each other; trusting the network itself and the contract code is sufficient.
Popular Application Areas
Decentralized Finance (DeFi): loans, exchanges, insurance, staking, and liquidity pools without intermediaries.
NFTs and Tokenization: digital asset ownership, secured transfer of ownership.
In general, smart contracts are designed to conclude agreements within a blockchain, create consensus, and fulfill predetermined parameters. The first smart contracts were created within the Ethereum blockchain.
