What are smart contracts?

Smart contracts are self-executing digital agreements written in computer code that exist on blockchain networks. They have become an essential technology in the continued emergence of cryptocurrency, playing a key role in the creation and inner workings of decentralized applications (DApps).

A closer look at smart contracts

Smart contracts are coded digital agreements written to blockchain networks. Once deployed, they typically cannot be changed or deleted. This technology significantly reduces the need for trusted intermediaries when creating and enforcing agreements. Unlike traditional contracts that require lawyers to draft and mediators to oversee disputes, smart contracts' terms are written in publicly auditable, immutable code that automatically executes when specific conditions are met.

These digital agreements serve as the building blocks of decentralized applications (DApps). Their interoperability allows them to be stacked, creating increasingly sophisticated products that function without oversight or involvement from intermediaries, including their creators. This characteristic has led to the term "money lego" being used to describe smart contract-based applications.

The origins of smart contracts

The concept of smart contracts was first proposed by Nick Szabo, a cryptographer, computer scientist, and early digital-money pioneer. In a 1994 essay, Szabo described computerized agreements that would automatically execute when predefined conditions were met. However, the technology to implement these ideas was not available at the time.

The creation of Bitcoin later provided the necessary technological foundation. While Bitcoin allows for simple smart contracts, more sophisticated programming languages are typically used for writing smart contracts on other blockchains. Platforms like Ethereum, Solana, Avalanche, Polkadot, and Cardano each support DApps built using smart contracts.

Ethereum, launched in 2015, is widely credited with bringing smart contracts to the crypto space. The project aimed to extend the functionality of the pioneering blockchain technology introduced by Bitcoin in 2009. Ethereum's smart contracts run on the Ethereum Virtual Machine (EVM), a digital software responsible for code execution and smart contract deployment.

How smart contracts work

Smart contracts are typically written in programming languages such as Solidity, Vyper, and Rust, with Solidity being the most popular for coding Ethereum-based smart contracts. These languages are used to build smart contracts with predefined rules and logic, often following an "if X happens, then do Y" structure.

Once written, the code is compiled into a machine-readable format called bytecode. The blockchain can understand bytecode and execute the rules of the smart contract accordingly. As users interact with a contract, the blockchain responds by automatically executing the correct action through a transaction. These transactions are paid for using gas fees.

How smart contracts are used

Smart contracts have become the cornerstone of much recent blockchain innovation. They have enabled developers to monetize digital artwork and collectibles, and are playing a crucial role in decentralizing the financial (DeFi) industry. Some notable examples of smart contract applications include:

1. Aave: A decentralized, non-custodial borrowing and lending protocol that allows users to earn returns and borrow assets by depositing assets into liquidity pools.

2. Civic: A personal identity verification service that provides secure and low-cost identity verification services, giving users total control over their personal identity information.

3. Decentralized exchanges: Leading platforms that rely on smart contracts for the smooth operation of liquidity pools within their automated market makers.

The final word

Smart contracts have become an integral part of the modern cryptocurrency space, serving as the foundation for decentralized applications and pioneering projects. By eliminating the need for centralized intermediaries, smart contracts support one of the core principles of cryptocurrency: decentralization. Their importance to the industry cannot be overstated, as they continue to enable new and innovative use cases across various sectors of the blockchain ecosystem.

FAQ

What is a smart contract in simple terms?

A smart contract is a self-executing digital agreement stored on a blockchain. It automatically enforces and executes predefined terms when specific conditions are met, without intermediaries.

Is bitcoin a smart contract?

No, Bitcoin itself is not a smart contract. However, Bitcoin supports basic smart contract functionality through its scripting language, enabling programmable transactions and features like multi-signature wallets.

What is a smart contract vs blockchain?

A smart contract is a self-executing digital agreement on a blockchain, automatically enforcing terms when conditions are met. Blockchain is the underlying decentralized, immutable ledger that records all transactions.

How does a smart contract get activated?

A smart contract activates when predefined conditions are met, automatically executing its code without human intervention. This often involves transferring funds or performing specific actions based on the contract's programmed logic.