Transactions

Blockchain FundamentalsUpdated: October 19, 2025
Also known as: Transaction, TX, Crypto Transaction
A transfer of value or data recorded on a blockchain, verified by network participants, and permanently added to the distributed ledger

A transfer of value or data recorded on a blockchain, verified by network participants, and permanently added to the distributed ledger.

Unlike traditional bank transfers that happen behind closed doors, crypto transactions are verified publicly and stored permanently on a blockchain. Once confirmed, they cannot be reversed, deleted, or altered.

How Crypto Transactions Work

When you send cryptocurrency:

  1. You initiate - You sign the transaction with your private key (like a digital signature)
  2. Network verifies - Miners or validators check that you have the funds and the signature is valid
  3. Gets recorded - Once verified, the transaction is added to a block on the blockchain
  4. Permanent - It stays on the blockchain forever

What's Different from Banks?

Bank Transfer

  • Processed by the bank
  • Can be reversed or canceled
  • Takes hours or days internationally
  • Private - only you and the bank see it
  • Closed on weekends and holidays

Crypto Transaction

  • Verified by network participants
  • Irreversible once confirmed
  • Settles in minutes (or seconds)
  • Public on the blockchain (identities are pseudonymous)
  • 24/7/365 - never closes

Types of Transactions

Simple Transfers

Sending Bitcoin or Ethereum from one wallet to another. The most basic type.

Smart Contract Interactions

Transactions that execute code on the blockchain - like swapping tokens on a DEX, minting an NFT, or staking coins.

Multi-Signature

Requiring multiple parties to approve before funds move - used by companies or DAOs for security.

Transaction Costs

Most blockchains charge a transaction fee (called "gas" on Ethereum) to compensate validators and prevent spam. Fees vary:

  • Bitcoin: $1-$50+ depending on congestion
  • Ethereum: $2-$100+ depending on gas prices
  • Solana: Fractions of a cent
  • Lightning Network: Pennies

Transaction Speed

Confirmation time varies by blockchain:

  • Bitcoin: ~10 minutes per block (wait 30-60 minutes for security)
  • Ethereum: ~12 seconds per block (1-2 minutes recommended)
  • Solana: ~400 milliseconds
  • Ripple: 3-5 seconds

Why Transactions Matter

Crypto transactions enable:

  • Peer-to-peer payments without banks
  • Cross-border transfers in minutes, not days
  • Programmable money via smart contracts
  • Transparency - anyone can audit the blockchain
  • Censorship resistance - no authority can block valid transactions

The Catch

Irreversibility is both a feature and a risk:

  • Send to the wrong address? Funds are gone forever
  • Victim of a scam? No chargeback available
  • Lose your private keys? Crypto is inaccessible

Double-check addresses before sending. "Not your keys, not your coins."

Real-World Use

Transactions power practical applications:

  • Remittances - Workers sending money home across borders
  • Stablecoin payments - Businesses settling invoices in USDC or USDT
  • DeFi - Lending, borrowing, trading without intermediaries
  • NFT purchases - Buying digital art, music, collectibles
  • Payroll - Some companies pay employees in crypto

Related Terms

  • Blockchain - The distributed ledger where transactions are recorded
  • Smart Contract - Self-executing code that processes complex transactions
  • Gas Fees - The cost to process transactions on networks like Ethereum
  • Mining - The process of verifying and adding transactions to the blockchain
  • Wallet - Software that stores your keys and lets you send/receive transactions