Sui uses objects as its basic unit of data storage rather than accounts, as happens on most other blockchains. Developers define, create, and manage these programmable objects that represent user-level assets. An object has distinct attributes, including ownership, whose values can be updated based on the governing logic of the smart contract that created it.Although a smart contract creates an object, it does not store the object. Objects and their attributes are stored directly on-chain.

Most assets on Sui are owned by a single address, recorded as a data value for the object. These are referred to as “owned objects.” Transferring ownership simply requires a change of that value. Transactions that are independent of any other action being performed on the network, such as an asset transfer, are considered simple or “single-writer” transactions and can be processed without going through consensus.Some assets have shared ownership, meaning multiple accounts must authenticate a transaction that changes data related to the object. These transactions are considered complex and must be validated through consensus.

Not only can a person own an object, but objects can own objects on Sui, allowing them to combine into a whole new asset, which is often referred to as composable assets.