Glossary of Arbitrum Terms
An address deterministically generated from an L1 contract address used on L2 to safely identify the source of an L1 to L2 message.
Arb Token Bridge
A series of contracts on an Arbitrum chain and its underlying chain that facilitate trustless movement of ERC-20 tokens between the two layers.
A suite of Ethereum layer-2 scaling technologies built with the Arbitrum Nitro tech stack that includes Arbitrum One (a live implementation of the Arbitrum Rollup Protocol) and Arbitrum Nova (a live implementation of the Arbitrum AnyTrust Protocol).
Arbitrum AnyTrust Chain
Arbitrum AnyTrust Protocol
An Arbitrum protocol that manages data availability with a permissioned set of parties known as the Data Availability Committee (DAC). This protocol reduces transaction fees by introducing an additional trust assumption for data availability in lieu of Ethereum's Trustless data availability mechanism. Arbitrum Nova is an example of an AnyTrust chain; Arbitrum One is an alternative chain that implements the purely trustless (and more L1-gas intensive) Arbitrum Rollup Protocol.
A blockchain that runs on the Arbitrum protocol. Arbitrum chains are EVM compatible, and use an underlying EVM chain (e.g., Ethereum) for settlement and for succinct fraud-proofs (as needed). Arbitrum chains come in two forms: Arbitrum Rollup Chains and Arbitrum AnyTrust Chains.
Arbitrum Full Node
A party who keeps track of the state of an Arbitrum chain and receives remote procedure calls (RPCs) from clients. Analogous to a non-staking L1 Ethereum node.
Current Arbitrum tech stack; runs a fork of Geth and uses WebAssembly as its underlying VM for fraud proofs.
The first Arbitrum AnyTrust Chain running on Ethereum mainnet. Introduces cheaper transactions; great for gaming and social use-cases. Implements the Arbitrum AnyTrust Protocol, not the Arbitrum Rollup Protocol protocol.
The first Arbitrum Rollup Chain running on Ethereum mainnet. Fully trustless; inherits Ethereum's base-layer security guarantees without introducing additional trust assumptions; great for decentralized finance and other use-cases that demand L1-level trustlessness.
Arbitrum Rollup Chain
Arbitrum Rollup Protocol
A trustless, permissionless Arbitrum protocol that uses its underlying base layer for data availability and inherits its security. This protocol is implemented by our Arbitrum One chain.
Arbitrum's "operating system" that trustlessly handles system-level operations; includes the ability to emulate the EVM.
A distributed digital ledger that is used to record transactions and store data in a secure, transparent, and tamper-resistant way, notably in cryptocurrency protocols.
🧢 CAP Finance
Widely considered the most degen community on Arbitrum.
CAP is a decentralized trading protocol. It's designed to be fast and easy to use by anyone.
A particular point in the history of an Arbitrum chain. A chain's state is determined by applying Arbitrum state-transition function to sequence of transactions (i.e., the chain's history).
When two Stakers disagree about the correct verdict on an Assertion, those stakers can be put in a challenge. The challenge is refereed by the contracts on the underlying chain. Eventually one staker wins the challenge. The protocol guarantees that an honest party will always win a challenge; the loser forfeits their stake.
Window of time (1 week on Arbitrum One) over which an asserted RBlock can be challenged, and after which the RBlock can be confirmed.
The protocol by which RBlocks are submitted, disputed, and ultimately confirmed. The Challenge Protocol guarantees that only valid RBlocks will be confirmed provided that there is at least one honest Active Validator.
An Arbitrum Chain that settles to an underlying Parent chain . For example, Arbitrum One and Arbitrum Nova are child chains of Ethereum.
A program running on a user's machine, often in the user's browser, that interacts with contracts on an Arbitrum chain and provides a user interface.
An action taken on some chain A which asynchronously initiates an additional action on chain B.
Short for "decentralized application." A dApp typically consists of smart contracts as well as a user-interface for interacting with them.
Data Availability Certificate
Data Availability Committee (DAC)
A permissioned set of parties responsible for enforcing data availability in an Arbitrum AnyTrust Protocol chain. See Introducing AnyTrust Chains: Cheaper, Faster L2 Chains with Minimal Trust Assumptions to learn more.
A shiny gem in the Arbitrum community.
Commonly associated with the esteemed Diamond Pepe's NFT and Dopex community. Dopex is a decentralized options exchange protocol on Arbitrum.
A software application used for transacting with the Ethereum Blockchain.
Fair Ordering Algorithm
BFT algorithm in which a committee comes to consensus on transaction ordering; current single-party Sequencer on Arbitrum may eventually be replaced by a fair-ordering committee.
Fast Exit / Liquidity Exit
A means by which a user can bypass an Arbitrum chain's Challenge Period when withdrawing fungible assets (or more generally, executing some "fungible" L2 to L1 operation); for trustless fast exits, a liquidity provider facilitates an atomic swap of the asset on L2 directly to L1.
The means by which an Active Validator proves to its underlying chain that an invalid state transition has taken place.
Gas Price Floor
A particular Custom gateway via which an L1 token contract can be registered to a token contract deployed to L2. A useful alternative to the StandardERC20 gateway for projects that wish to control the address of their L2 token contract, maintain L2 token contract upgradability, and for various other use-cases.
An execution-layer client that defines the Ethereum state transition function and handles network-layer logic like transaction memory pooling. Arbitrum Nitro utilizes a fork of Geth to implement Arbitrum's state transition function.
If you've seen some blueberries wandering around on crypto Twitter, you might wonder .. where did they come from?
The iconic blueberries come from the community of the decentralized exchange, GMX.
Data structure that represents a group of L2 transactions (analogous to L1 blocks).
L2 to L1 Message
A message initiated from within an Arbitrum chain to be eventually executed on Layer 1 (L1) (e.g., token or Ether withdrawals). On Rollup chains like Arbitrum One, the Challenge Period must pass before an L2 to L1 message is executed.
Layer 1 (L1)
The base protocol and underlying blockchain of the Ethereum network. Responsible for maintaining the integrity of the distributed ledger and executing smart contracts. Contains both Ethereum's execution layer and consensus layer.
Layer 2 (L2)
Trustless scaling solutions built on top of Ethereum's Layer 1 (L1) base protocol, such as state channels, plasma chains, optimistic rollups, and ZK-rollups. Layer 2 solutions aim to increase scalability and reduce the cost of transactions on Ethereum's Layer 1 without introducing additional trust assumptions.
Layer 3 (L3)
An Arbitrum chain whose core contract reside on an Arbitrum Layer 2 (L2) chain.
One Step Proof
Final step in a challenge; a single operation of the Arbitrum VM (WASM ) is executed on the underlying chain, and the validity of its state transition is verified.
An L1 contract responsible for tracking L2 to L1 Messages, including withdrawals, which can be executed once they are confirmed. The outbox stores a Merkle Root of all outgoing messages.
EVM compatible chain that acts as the settlement layer for one or more Arbitrum Chains (aka Child chain ). E.g., Ethereum is the parent chain of both Arbitrum One and Arbitrum Nova. Parent chain is synonymous with "underlying chain."
🏴☠️ Pirate Nation
If you sail in the deep blue seas of Arbitrum, you may encounter some ships with pirate flags along the way ARRGG!
The pirate flag originates from the Pirate Nation community. Pirate Nation is a game filled with high seas adventure, treasure, fun, and unexpected surprises.
An assertion by an Arbitrum Validator that represents a claim about an Arbitrum chain's state.
The "automatic" (i.e., requiring no additional user action) execution of a Retryable Ticket on an Arbitrum chain.
An L1 to L2 cross chain message initiated by an L1 transaction sent to an Arbitrum chain for execution (e.g., a token deposit).
Reverse Token Gateway
A Token Gateway in which the Child chain gateway contract escrows and releases tokens, which the Parent chain Gateway contract mints and burns tokens. This in the inverse to how "typical" gateways work.
An entity (currently a single-party on Arbitrum One) given rights to reorder transactions in the Fast Inbox over a fixed window of time, who can thus give clients sub-blocktime Soft Confirmations. (Not to be confused with a Validator).
A computer program whose operations are defined and executed within a blockchain consensus protocol.
Near the core of Arbitrum community is Smolverse, a world filled with Smol Brains and Smol Bodies.
If you see any Smol's with giga brains, swole arms or hear the sound of "EEEE" in the Arbitrum community, you've encountered the Smol Brains and Smol Bodies.
A semi-trusted promise from the Sequencer to post a user's transaction in the near future; soft-confirmations happen prior to posting on the Parent chain, and thus can be given near-instantaneously (i.e., faster than the parent chain's block times)
A Validator who deposits a stake (in Ether on Arbitrum One and Arbitrum Nova ) to vouch for a particular RBlock in an Arbitrum Chain. A validator who stakes on a false RBlock can expect to lose their stake. An honest staker can recover their stake once the RBlock they are staked on has been confirmed.
An token contract on an Arbitrum chain deployed via the StandardERC20 gateway; offers basic ERC20 functionality in addition to deposit / withdrawal affordances.
🏹 Tales of Elleria
The bow and arrow are commonly associated with the Hero's of Tales of Elleria.
Jump into the world of Elleria and go on adventures.
A proposed (not currently live) transaction policy in which users can pay a fee to the Sequencer for a small ordering advantage. See [here](https://medium.com/offchainlabs/time-boost-a-new-transaction-ordering-policy-for-arbitrum-5b3066382d62) for more.
Hidden in the Croakshire, you will find the friendly Toadstoolz.
The iconic Toads of Arbitrum love to hunt BUGZ
and collect NFTs. !CROAK
A pair of contracts in the token bridge — one on the Parent chain , one on the Child chain — that provide a particular mechanism for handling the transfer of tokens between layers. Token gateways currently active in the bridge include the StandardERC20 gateway , the Generic-Custom Gateway , and the WETH Gateway.
If you see some homes along your road trip in the Arbitrum ecosystem, you've made it to TownStory.
Build a warm and prosperous town with friends in TownStory.
A user-initiated interaction with a Blockchain. Transactions are typically signed by users via wallets and are paid for via transaction fees.
✨ Treasure DAO
While exploring the Arbitrum ecosystem, you may see some shining stars.
The iconic stars symbolize the magic of Treasure DAO. Treasure DAO is the decentralized gaming ecosystem connecting games and players on Arbitrum.
In the context of Ethereum, trustless refers to the ability of a system to operate without reliance on a central authority or intermediary. Instead, users place their trust in math and protocols.
This is achieved through the use of cryptographic techniques and decentralized consensus mechanisms that let users verify the integrity of network transactions using open-source software. Trustless systems are considered to be more secure and resistant to fraud or tampering because they don't rely on a single point of failure that can be exploited by attackers.
Synonymous with Parent chain.
Widely supported binary code format for executable programs. Used by Arbitrum Nitro for Fraud proofs , and more broadly used by Stylus to support performant smart contracts in a wide variety of languages.
A Validator that never stakes / never takes on chain action, who raises the alarm (by whatever off-chain means it chooses) if it witnesses an invalid assertion.
Token Gateway for handing the bridging of wrapped Ether (WETH). WETH is unwrapped on L1 and rewrapped on L1 upon depositing (and vice-versa upon withdrawing), ensuring WETH on L2 always remains collateralized.
As you're exploring the Arbitrum world, you may bump into a world filled with monsters and Zee's.
Explore a mythical Spirit Realm as a young Shaman and take part in strategic turn-based battles to help protect Zeeverse from the looming corrupted forces.