Ripple is a global payment protocol aimed to provide fast transactions and cheap payments internationally. The network uses a digital currency known as XRP (sometimes it's referred to as Ripple). Unlike other cryptocurrencies Ripple is not aimed to replace banks, rather this project is created to improve the work of banks (including transactions between different banks) via blockchain solutions.
Dropil (DROP) is an Ethereum token and works as a utility token for the Dropil platform. No more Dropil tokens will ever be created, which is supposed to prevent further deflation. You can buy Dropil (DROP) for cryptos (for example, BTC or ETH) with some exchange platforms.