Ethereum and Ripple are two of the most significant cryptocurrencies besides Bitcoin. While Ethereum makes it easier for developers to create applications using smart contracts, Ripple makes cross-border financial transfers faster, cheaper, and more efficient. Some key differences between the two cryptocurrencies are: 1) Ripple can process over 1,000 transactions per second compared to Ethereum's 15 transactions per second, though Ethereum 2.0 may increase its speed; 2) There is a fixed supply of 100 billion Ripple coins compared to Ethereum's unlimited supply; 3) Ripple uses a consensus mechanism called Federated Byzantine Agreement while Ethereum currently uses Proof-of-Work but is transitioning to Proof-of-St