What are bitcoin smart contracts (DLCs)?

Bitcoin smart contracts (also known as discreet log contracts) enable conditional (oracle-based) contracts on bitcoin. The way it works is that each party to a contract creates and shares encrypted signatures for each output condition to the contract. Each counterparty has confidence they can decrypt the encrypted signatures and use them correctly at the right time because they can verify the encryption: verify when they can decrypt the signatures and that the signatures are valid.

Bitcoin smart contracts are a better way to do smart contracts because they are secure, private, customizable, and scalable. They mitigate bug risk because they are formally verified, meaning the output conditions of the contract are known from the beginning. This helps avoid exploits you constantly see in Ethereum. Since these contracts use off-chain oracles, they aren't susceptible to oracle manipulation by miners. Not only that, but these contracts are private, customizable (choose your own oracle), and scalable (minimal on-chain cost because execution happens off-chain).

These contracts are zero knowledge in that the blockchain has zero knowledge about the contract, the oracles have zero knowledge about the contract, and the counterparty can verify the encryption without needing the decrypted material.

Lava's DLC implementation is open-source and can be found here.