# Blockchain

> A blockchain is a distributed ledger that uses cryptography to validate transactions.

Source: https://metavert.io/blockchain  
Published: 2026-01-22  
Updated: 2026-03-10

[**Megatrend**](https://metavert.io/megatrends)

A blockchain is a distributed ledger that uses [public key cryptography](https://metavert.io/public-key-cryptography) to validate transactions. The advantage of blockchain is that financial transactions can be recorded in a **decentralized**, **trustless**, and **permissionless** manner, without requiring any central authority to control it.

The cryptographic foundation is [asymmetric encryption](https://metavert.io/public-key-cryptography): each participant holds a private key (kept secret) and a corresponding public key (shared openly). Transactions are digitally signed with the sender's private key and verified by anyone using their public key — this is what enables [trustless](https://metavert.io/trustless) operation without intermediaries. The same cryptographic primitives underpin [smart contracts](https://metavert.io/smart-contract), [self-sovereign identity](https://metavert.io/selfsovereign-identity), and emerging [content authenticity](https://metavert.io/content-authenticity) standards like [C2PA](https://metavert.io/c2pa).

The first major blockchain application was the cryptocurrency Bitcoin, invented by pseudonymous creator Satoshi Nakamoto in 2009. In 2015, the Ethereum blockchain introduced [**smart contracts**](https://metavert.io/smart-contract), enabling programmatic exchanges of value: for the first time, code could exchange currencies and assets with other code, much as the World Wide Web allows code to exchange information.

Smart contracts enabled entirely new categories of decentralized software: [**decentralized finance (DeFi)**](https://metavert.io/decentralized-finance) with $140–150 billion in total value locked, **decentralized autonomous organizations (DAOs)**, and [**non-fungible tokens (NFTs)**](https://metavert.io/non-fungible-token). The broader [Web3](https://metavert.io/web3) ecosystem has reached approximately $3.2 trillion in total market value as of early 2026, driven by institutional adoption, stablecoins surpassing $310 billion in market cap, and Layer-2 scaling solutions that dramatically reduce transaction costs.

Early blockchains including Bitcoin used proof-of-work algorithms requiring substantial energy. Ethereum's transition to proof-of-stake in 2022 reduced its energy consumption by over 99%, and most modern blockchains use similarly efficient consensus mechanisms. Layer-2 solutions like Arbitrum, Optimism, and Base have brought transaction costs to fractions of a cent while inheriting the security guarantees of their parent chains.

The most significant recent evolution has been the tokenization of real-world assets (RWA)—bringing traditional financial instruments, real estate, and commodities onto blockchain infrastructure. NFTs have similarly matured from speculative art trading toward utility-driven applications including digital ticketing, loyalty programs, and financial vouchers.

## Related Topics

- [Public Key Cryptography](https://metavert.io/public-key-cryptography)
- [Smart Contract](https://metavert.io/smart-contract)
- [Decentralization](https://metavert.io/decentralization)
- [Non-Fungible Token](https://metavert.io/non-fungible-token)
- [Web3](https://metavert.io/web3)
- [Decentralized Finance](https://metavert.io/decentralized-finance)
- [Zero Knowledge Proofs](https://metavert.io/zero-knowledge-proofs)

## Further Reading

- [9 Megatrends Shaping the Metaverse](https://meditations.metavert.io/building-the-metaverse/9-megatrends-shaping-the-metaverse-93b91c159375)
- [Money, Blockchains and Social Scalability](http://unenumerated.blogspot.com/2017/02/money-blockchains-and-social-scalability.html) (Nick Szabo)
- [Smart Contracts: the Ultimate Guide for Beginners](https://101blockchains.com/smart-contracts/)