Decentralized applications (dApps) are applications that run on blockchain networks rather than centralized servers. They leverage the decentralized and immutable nature of blockchains to provide various services, including finance, gaming, and social networking. dApps operate using smart contracts, ensuring transparency and trustworthiness. Examples of popular dApps include Uniswap for decentralized trading, CryptoKitties for blockchain-based gaming, and Steemit for decentralized social media. The growth of dApps represents a shift towards more open and decentralized internet services.