Blockchain Basics
Intro to distributed ledger tech.
A blockchain is a database where data is stored in blocks that are chained together. Each block contains a hash of itself and the previous block, ensuring immutability. It is typically decentralized, meaning consensus is reached by a global node network. In 2026, the focus has moved from simple ledgers to modular storage and data availability layers.
graph LR
Center["Blockchain Basics"]:::main
Pre_cryptography["cryptography"]:::pre --> Center
click Pre_cryptography "/terms/cryptography"
Pre_distributed_systems["distributed-systems"]:::pre --> Center
click Pre_distributed_systems "/terms/distributed-systems"
Rel_layer_1["layer-1"]:::related -.-> Center
click Rel_layer_1 "/terms/layer-1"
Rel_distributed_ledger_technology_dlt["distributed-ledger-technology-dlt"]:::related -.-> Center
click Rel_distributed_ledger_technology_dlt "/terms/distributed-ledger-technology-dlt"
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🧒 Explain Like I'm 5
Imagine a shared notebook that everyone can write in, but once a page is finished, it's locked forever and everyone gets a copy. No one can erase what's written, so everyone knows exactly what happened and when.
🤓 Expert Deep Dive
Core tech includes Cryptographic [Hashing](/en/terms/cryptographic-hashing) (SHA-256), [Public-Key Cryptography](/en/terms/public-key-cryptography) (ECDSA), and P2P Networking. The system solves the Byzantine Generals Problem using economic incentives. Modern developments separate data availability from execution to solve the scaling trilemma.