Arbitrum is an L2 scaling blockchain for Ethereum. Arbitrum was created by Offchain Labs, a New York, United States-based company.
Arbitrum uses a method called optimistic rollup, a data compression technique for blockchain transactions. This allows Aribtrum to save time and fees, as multiple transactions are confirmed in one single transaction (the rolled-up transaction).
Currently, Arbitrum does not have a native token. Arbitrum's investors include Lightspeed Venture Partners, Polychain Capital, Ribbit Capital, Redpoint Ventures, Pantera Capital, Alameda Research, and Mark Cuban, among others.