What a cryptocurrency actually is
A cryptocurrency is a unit of value recorded on a blockchain — a shared, append-only ledger maintained by a network of participants rather than a single institution. Some cryptocurrencies are native to their chain: Bitcoin (BTC) is the native asset of the Bitcoin network, Ether (ETH) of Ethereum. Others are tokens issued on an existing chain under a token standard — an ERC-20 token on Ethereum, a TRC-20 token on Tron, or an SPL token on Solana — including the dollar-pegged stablecoins most often used for payments.
What makes it spendable is the key pair behind every account. The holder controls a private key; the matching address is where funds sit on the ledger. To pay, the holder signs a transaction with that private key, and the network's validators verify the signature, confirm the funds exist, and record the transfer in a block. No intermediary has to authorise it — that is the meaning of peer-to-peer. Once the transaction is confirmed and final, the ledger reflects the new owner and the move cannot be reversed by a third party.
Because the asset is defined by the chain it lives on, it inherits that chain's properties: how fast a transaction confirms, what a transaction fee (gas) costs, and how many confirmations are prudent before treating a payment as settled. The same kind of asset — a dollar stablecoin, say — can exist on several chains, and the chain it rides determines its speed and cost rather than its value.
Why it matters for crypto payments
For a merchant, the defining trait of a cryptocurrency payment is that it settles directly on a public network with no card scheme or bank in the middle. That removes the intermediaries that can hold, reverse, or decline a payment, and it makes the payment reach across borders without a correspondent banking chain. The trade-off is that the merchant — or a provider acting for them — has to deal with the chain directly: watch for the deposit, wait for enough confirmations, and account for the asset received.
Not all cryptocurrencies behave the same way at checkout. A freely-floating asset like Bitcoin or Ether can move in price between the moment a customer is quoted and the moment the payment clears, which is why many customers and merchants prefer a stablecoin — a cryptocurrency engineered to track a fiat currency — so the amount paid maps cleanly to the amount billed. The practical question for a merchant is rarely 'crypto or not' but 'which asset, on which chain, with what confirmation behaviour'.
Cryptocurrencies on halfin
halfin lets an online business accept a defined set of cryptocurrencies and settle them on-chain. It supports the native assets BTC, ETH, BNB, TRX, XRP and SOL, and the stablecoins USDT and USDC on the networks where each has the liquidity that matters for payments — USDT on Tron (TRC-20), Ethereum (ERC-20) and Solana; USDC on Ethereum (ERC-20), Solana and Base. A customer pays whichever supported asset they hold on whichever supported chain suits them, and it credits to the merchant's balance for that asset.
halfin invoices are fiat-anchored: the merchant bills a fiat amount in a fiat currency, and halfin maps that figure to the payable cryptocurrency amount at the live rate and locks it when the invoice activates. That keeps the volatility of a floating asset off the merchant's books — the ledger records the fiat figure that was billed, regardless of how the underlying coin moved. Crediting is reorg-aware and waits for each chain's confirmation threshold before the invoice is marked paid, so a deposit undone by a chain reorganization never leaves a paid invoice behind.
From there, a cryptocurrency balance flows through the platform like any asset: convert between assets through balance conversion, send funds out through single or mass payouts, or return money to a customer through a refund. halfin does not sell crypto to end users — it is payment infrastructure for receiving, settling, and moving the cryptocurrencies a business is paid in.
- Native and issued — supported native assets (BTC, ETH, BNB, TRX, XRP, SOL) plus stablecoins (USDT, USDC) issued on supported chains.
- Peer-to-peer settlement — payments settle on-chain with no card scheme or bank in the middle, and a confirmed, final payment cannot be reversed.
- Chain decides speed and cost — the same asset on a different chain confirms at a different pace and carries a different transaction fee.
- Fiat-anchored — bill in fiat, the customer pays the equivalent cryptocurrency amount, and the ledger records the fiat figure at the locked rate.