ATOM is the proof-of-stake token that powers the Cosmos Hub, the central blockchain of the entire Cosmos platform. ATOM is used to pay for transaction fees on the platform, stake to secure the network, and participate in protocol governance.

Cosmos is a decentralized network of independent parallel blockchains that creates an ecosystem of interconnected blockchains that can scale, operate, and communicate with each other. Cosmos uses the Tendermint BFT consensus mechanism, enabling developers to build application-specific blockchains using the Cosmos SDK without creating a consensus mechanism from scratch. Cosmos has a “Hub and Spoke” style architecture, with sidechains/Zones connected to central Hubs that act as routers that connect Zones to each other. This, in essence, creates an “Internet of Blockchain” wherein an independent blockchain is connected to all other Zones through a single connection. Asides from interoperability within the Cosmos ecosystem, Cosmos is also interoperable with external blockchains and supports ETH, BTC, ALGO, and more at the moment using Peg Zones.

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