Building decentralized applications implies that they run in a peer-to-peer network of computers rather than on a single computer.
They run on a P2P network of computers running on a network of computers instead of a single computer, i.e. they are decentralized. The power is not concentrated in one place; it is distributed among several computers simultaneously. This means that none of the users can control the operation of the program. For example, instead of using a centralized cloud storage system such as Dropbox, customers can use decentralized storage networks such as Storj.io and Interplanetary File System (IPFS) to store files and data.
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