Cosmos is a decentralized network of independent parallel blockchains, each powered by Tendermint's BFT consensus algorithm.
Prior to Cosmos, blockchains operated independently with decentralized Apps (dApps) written as smart contracts on top. However, thanks to the open source tools implemented by Cosmos, Tendermint, Cosmos SDK, and IBC, blockchain developers are enabled to easily build high performing and secure blockchains that can scale and interoperate with others in the Cosmos ecosystem.
Cosmos marries the spirit of collaboration to the innovation of blockchain. Developers within the Cosmos community are encouraged to improve existing tools and create new ones in order to fulfill the promise of blockchain technology.