What Is Blockchain? A Simple Explanation for Beginners
A blockchain is a shared record of transactions that many computers keep in sync, so no single party can quietly rewrite history.
How a Blockchain Records Data
A transaction is requested and broadcast to a peer-to-peer network. Nodes validate it using the network's consensus rules, group it with other verified transactions into a block, and append that block to the chain.
Because each block references the one before it, changing an old record would require redoing all the work that followed it across the whole network.
Uses Beyond Cryptocurrency
Blockchains are used for supply-chain tracking, digital identity, ownership records, and settling payments between institutions — anywhere multiple parties need one shared version of the truth.
Frequently Asked Questions
Is blockchain the same as Bitcoin?
No. Bitcoin is one cryptocurrency that uses a blockchain. Blockchain is the underlying record-keeping technology, and thousands of projects use it differently.
Why is a blockchain considered secure?
Records are cryptographically linked and copied across many independent computers, so altering past data would require overpowering the majority of the network at once.