An open cryptographic protocol that allows applications to make transactions with and run smart contracts in a secure and decentralized fashion. The Celo Blockchain code has shared ancestry with Ethereum, and maintains full EVM compatibility for smart contracts. However it uses a Byzantine Fault Tolerant (BFT) consensus mechanism rather than Proof of Work, and has different block format, transaction format, client synchronization protocols, and gas payment and pricing mechanisms.
Mainnet - https://explorer.celo.org/
AlfajoresTestnet - https://alfajores-blockscout.celo-testnet.org/
Backlava Testnet - https://baklava-blockscout.celo-testnet.org/
Mainnet = https://rc1-forno.celo-testnet.org
Alfajores - https://alfajores-forno.celo-testnet.org
Baklava = https://baklava-forno.celo-testnet.org
Celo is based on Ethereum implementation, so the API is similar to the Ethereum RPC API. In addition to Ethereum, Celo has an Contrakt Kit API.
Official RPC documentation: https://eth.wiki/json-rpc/API
Contract Kit API: https://docs.celo.org/developer-guide/overview/introduction/contractkit