What Arbitrum Is
Arbitrum's own documentation describes it as the finance-native platform providing infrastructure for applications, tokenization and dedicated chains. In practice it is best known as a layer 2 network that runs on top of Ethereum so transactions are cheaper and faster, while relying on Ethereum for security. The documentation names Arbitrum One and Arbitrum Nova as chains, and Arbitrum Stylus, which lets developers write smart contracts in languages such as Rust and C.
The 2023 Airdrop
The Arbitrum Foundation announced that its new ARB token would be airdropped to community members on March 23, 2023. Eligibility was based on a snapshot of onchain activity taken in February, built with analytics firm Nansen, which weighed things like how many transactions a user made, how many different applications they used and how long they had been on Arbitrum. The airdrop allocated 11.5% of ARB's total supply to eligible users and 1.1% to DAOs operating in the Arbitrum ecosystem. Investors and employees of Offchain Labs, the firm that built Arbitrum, received 44% of the total supply.
A Token for Governance, Not Gas
ARB marked Arbitrum's official transition into a decentralized autonomous organization (DAO), so ARB holders can vote on key decisions governing Arbitrum One and Arbitrum Nova. Unlike ETH on Ethereum, ARB is not used to pay transaction fees; its role is governance.
What Happened to Unclaimed Tokens
The 2023 claim window has passed. The Block reported at the time that unclaimed airdrop tokens flowed to the Arbitrum DAO treasury.
What to Weigh Before Using It
Airdrops attract scams. Any site, message or social post offering a new Arbitrum airdrop claim should be treated with suspicion, since the 2023 distribution is over and the real announcements come from the project's official channels. Never connect a wallet to an unfamiliar claim page or approve unknown contracts, and remember that being eligible for a past airdrop says nothing about whether a future token will be worth anything. Start small, read the project's current documentation for the exact product you plan to use, and only commit money you can afford to lose. This summary is educational and not financial advice.