Testnet faucets are online platforms that provide users with free testnet tokens for testing and experimentation purposes. These faucets enable developers and users to acquire testnet tokens without the need for purchasing or mining them. By using testnet faucets, users can simulate real cryptocurrency transactions on a test network without spending real money. Testnet faucets play a crucial role in facilitating the development and testing of decentralized applications (dApps) and smart contracts before deploying them on the mainnet. They provide a valuable resource for developers to ensure the smooth functioning of their projects before going live.