Parachain
Web3 / blockchain technology
A sovereign blockchain running in parallel to the Polkadot or Kusama relay chain, connected to it via a slot mechanism that allows parachains to share the security of the relay chain's validator set without needing their own independent validator network. Parachains can have their own tokens, governance, and custom logic while benefiting from Polkadot's pooled security—a design that addresses the bootstrapping problem facing new chains that lack sufficient validator decentralization on their own. Parachain slots are secured via candle auctions where projects bid DOT tokens. Each parachain can specialize: Moonbeam is an EVM-compatible parachain, Acala is the DeFi hub, and Interlay provides cross-chain Bitcoin integrations. Parachains communicate with each other via XCM (Cross-Consensus Messaging), Polkadot's native cross-chain protocol. Example: Acala won its Polkadot parachain slot in December 2021 through a crowdloan where DOT holders contributed their tokens to Acala's bid in exchange for ACA token rewards, raising over 32 million DOT (then worth approximately $1.3 billion) to secure the slot. Why it matters for Web3: Parachains represent one architecture for a multi-chain future, enabling specialized application-specific blockchains to inherit security from a shared parent chain without the full cost of bootstrapping independent validator sets, a model being tested at scale in the Polkadot ecosystem.
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