Understand crypto.
Keep it simple.

A shared ledger that orders operations in cryptographically linked blocks. Participants verify network rules; decentralisation varies between blockchains.

Example: a confirmed transaction can be looked up in a public block explorer.

A digital asset whose transfers use cryptography and usually a blockchain. Its price can fluctuate sharply; the name does not make it legal tender.

Example: BTC is the native asset of the Bitcoin network.

Bitcoin is a network for transferring value; bitcoin, or BTC, is its native asset. Its protocol specifies a maximum supply of 21 million BTC.

Example: you can send a fraction of a bitcoin without owning a whole BTC.

Ethereum is a blockchain that runs programs called smart contracts. Ether, or ETH, is used to pay fees and participate in network security.

Example: swapping tokens on Ethereum uses a smart contract.

A coin is generally a blockchain’s native asset. A token is issued on existing infrastructure. Uses vary: payments, governance or representing a right.

Example: ETH is native to Ethereum; an ERC-20 token uses that network.

An application or device for viewing assets and authorising operations. In self-custody, the wallet manages keys; assets remain recorded on the network.

Example: changing wallet apps does not automatically move assets to another blockchain.

A destination identifier for receiving an asset on a particular network. It can be shared for payment, but may expose a public transaction history.

Example: check the address, network and token together before sending.

A cryptographic secret used to sign operations. Someone who obtains it can generally control the associated assets; never give it to a support agent.

Example: signing a transfer authorises an operation without sending the key to the recipient.

A sequence of words that can restore many wallets and their derived keys. It gives broad access to assets; some wallets use other recovery methods.

Example: keep it offline and never enter it on a link received in a message.

A signed instruction sent to a network: a transfer, a program call or another operation. Its hash is a tracking identifier; it does not by itself prove success or finality.

Example: an explorer distinguishes pending, failed and confirmed transactions.

Gas measures the work requested on Ethereum and some similar networks. Cost depends on gas used and the gas price; even a failed operation can incur fees.

Example: swapping a token may cost more than a simple ETH transfer.

A computer running network software. Depending on its role and type, it verifies, relays or stores data. Not every node produces blocks.

Example: a full node checks blocks against protocol rules.

Mechanisms that let participants agree on a valid history despite delayed messages or malicious actors. It is not an informal vote on every payment.

Example: Bitcoin uses proof of work; Ethereum uses proof of stake.

Miners perform computational work to propose blocks under a network’s rules, as on Bitcoin. Other participants verify those blocks; mining consumes energy.

Example: Bitcoin miners receive the scheduled issuance and transaction fees.

Validators commit assets to help secure a proof-of-stake network. Rewards and risks depend on the protocol and service; this is not a guaranteed savings account.

Example: an Ethereum validator can incur penalties depending on its behaviour.

A program deployed on a blockchain that executes rules when called. It can automate an exchange, but bugs or unsafe permissions can cause losses.

Example: a program swaps two tokens when its conditions are met.

A cryptoasset designed to track a reference, often a currency. Stability depends on its mechanism, issuer and, where applicable, reserves and redemption terms.

Example: targeting one dollar guarantees neither a permanent peg nor an insured bank deposit.

A buying and trading service operated by a company. It may custody customer assets and controls account access under its terms.

Example: buying with euros and withdrawing to a personal address are separate operations.

A protocol for swapping assets through smart contracts, often from a wallet. Risks include bugs, fake tokens, low liquidity and token approvals.

Example: a swap can fail if the price moves beyond the selected tolerance.

Financial services built with protocols and smart contracts: trading, lending and other mechanisms. Technical openness does not remove financial, legal or software risks.

Example: a collateralised loan can be liquidated if the collateral becomes insufficient.

An individually identifiable token that is not interchangeable on identical terms with another. It may represent an item or right; owning it does not automatically confer copyright over a file.

Example: a ticket can be associated with an NFT under the organiser’s terms.

A system that processes operations above a base blockchain and relies on it for aspects of security. Fees, withdrawal delays and guarantees depend on its design.

Example: a rollup batches operations before submitting data or proofs to Ethereum.

A mechanism for moving assets or messages between networks, sometimes by creating a representation of an asset. It adds its own security assumptions and risks.

Example: the same token symbol on two networks does not guarantee the same issuer or contract.

An estimate calculated by multiplying a price by circulating supply. It differs from fully diluted valuation, which uses a broader supply measure.

Fictional example: €2 × 10 million tokens = €20 million; this is not money actually invested.

How easily an asset can be bought or sold without substantially moving its price. Past volume, market depth and order size are distinct concepts.

Example: a large order in a small market can execute at a much less favourable price.