Glossary
Optimism
An optimistic rollup and the home of the OP Stack — a modular open-source rollup framework used by Base, World Chain, Zora, and others.
Optimism is an optimistic rollup launched in late 2021 by the OP Labs team. The OP Stack — its open-source rollup framework — has become the most-used base for new EVM L2s, including Coinbase's Base, World Chain, Zora, and Mantle.
Chains built on the OP Stack interconnect via the "Superchain": a shared protocol layer with common bridges, sequencing, and (in roadmap) shared sequencing. OP itself is the governance token of the Optimism Collective.