Omni is an open-source and decentralized asset platform layer built on top of the Bitcoin blockchain. Omni also has a reference implementation called the Omni Core, which is a fork of the Bitcoin Core that adds the full functionality and features of the Omni Layer. Users can create and trade their own digital assets on the Omni platform. Crowfunds can be started on the Omni layer and its blockchain for these created digital assets, and users can then send these assets peer-to-peer over the Bitcoin blockchain and even create their own decentralized exchange. The Omni Layer powers all of these features through the use of smart contracts.
Omni (OMNI) is the primary digital asset of the Omni platform, and it can sent peer-to-peer over Bitcoin and used to power the smart contracts (and thus the creation of other digital assets).