Token
A unit of value or rights recorded on a blockchain, usually created by a smart contract rather than by the chain itself.
A token is a row in a smart contract's ledger: the contract stores how many units each address holds, and its code defines the rules for transferring them. Because the token lives on a host blockchain, moving it requires paying that chain's transaction fee in the chain's own native asset. Tokens are a container, not a category of value: the same technical form is used for stablecoins, governance rights, receipts for deposited collateral, collectibles, and points. Readers meet tokens as a contract address plus a symbol, and two different contracts can use the same symbol, which is why wallets and data sites key off the address.
In practice
A stablecoin such as USDC and a governance token such as UNI are both tokens on Ethereum: their balances live inside separate smart contracts, while the fee to move either one is paid in ether.
The common misunderstanding
Holding a token rarely means owning a legal share of anything; unless a separate contract or legal agreement says otherwise, it is a ledger entry carrying only the rights the code and the issuer choose to give it.