Bitcoin (Abbreviation: BTC; sign: ₿) is a decentralized digital currency that can be transferred on the peer-to-peer bitcoin network.
Cardano is a public blockchain platform. It is open-source and decentralized, with consensus achieved using proof of stake.
Ethereum is a decentralized, open-source blockchain with smart contract functionality. Ether is the native cryptocurrency of the platform.
Tether (often referred to by one of its currency codes, USD₮), is an asset-backed cryptocurrency stablecoin. It was launched by the company Tether Limited Inc.