Decentralized applications are applications, just like those you download on your phone or PC, except that they run on a network of computers instead of relying on a single computer.
The benefits of dApps include the safeguarding of user privacy, the lack of censorship, and the flexibility of development.
DApps can be developed for a variety of purposes including gaming, finance, and social media.
For example, a developer can create a Twitter-like dApp and put it on a blockchain where any user can publish messages. Once posted, no one—including the app creators—can delete the messages.
Content from Investopedia.