MultiChain

MultiChain is a platform to build permissioned blockchain-based DApps. Unique features of MultiChain include permissions management, data streams, and assets. It doesn't support smart contracts. This is an example of a non-smart contract-based platform for building blockchain-based DApps. MultiChain uses round robin validation consensus. 

Initially MultiChain was based on the idea of managing ownership and transfer of assets on blockchain. Operations on assets includes issuance, reissuance, transfer, atomic exchange, escrow, and destruction of assets. Later on, data streams were introduced to provide a different flavor of representing data in MultiChain. Any number of streams can be created in a MultiChain, and each stream acts as an independent append-only collection of items. Operations on streams include creating streams, writing, subscribing, indexing, and retrieving. So, basically, a blockchain use case on MultiChain can be built on a foundation of assets or streams. Finally, permission management is used to control who can connect, transact, create assets/streams, mine/validate, and administrate. 

MultiChain provides maximal compatibility with the Bitcoin ecosystem, including the peer-to-peer protocol, transaction/block formats, the UTXO model, and Bitcoin Core APIs/runtime parameters. So, before you start learning MultiChain, it's better to learn how Bitcoin works at a high level at least.