What is a blockchain
A blockchain is a network of computers that jointly maintain a shared record of transactions. Each blockchain is its own independent network — a token on Ethereum and a token on Polygon are not interchangeable unless explicitly moved between them. When you send a transaction or interact with a protocol, you do so on a specific chain. Sending tokens to the wrong chain means they can be lost.Supported chains
Cobo Agentic supports two categories of chains: EVM-compatible chains and Solana. These categories differ in address format, token standard, and contract interaction model — see EVM vs. Solana for a full comparison.EVM chains
EVM chains follow the same technical rules as Ethereum and use a numeric chain ID to identify each network. Each EVM chain has a unique numeric chain ID so tools know which network you’re on.Solana
Solana uses a cluster name rather than a numeric chain ID to identify each network.EVM vs. Solana
Cobo supports both EVM-compatible chains and Solana. These two ecosystems work differently:
See Smart contracts for more on how contract calls work on each chain type.
Layer 2 chains
Some EVM chains — including Base, Arbitrum, and Optimism — are Layer 2 (L2) chains. They process transactions faster and more cheaply than Ethereum mainnet by handling activity off the main chain, then periodically recording a summary back to Ethereum for security. From a user’s perspective, L2 chains work just like Ethereum: same address format, same token standards, same contract interaction model. The main practical differences are:- Gas fees on L2 are typically 10–100× cheaper than Ethereum mainnet.
- Bridge exits back to Ethereum vary by rollup type: optimistic rollups (Base, Optimism) require a challenge period of up to 7 days; ZK rollups can settle in minutes to hours.
- Protocols like Uniswap deploy separate contracts on each L2 — the contract addresses differ across networks.