A
ABI
ABI stands for application binary interface. It is a set of rules dictating how software components interact with each other at the binary level, which is different from an API that interacts at the source code level.
In a Web3 context, an ABI defines how to encode and decode data from a smart contract.
Address
Often referred to as a “wallet,” a crypto address is a unique set of alphanumeric characters that can send and receive cryptocurrency and NFTs on a blockchain.
Airdrop
Airdrops are used to distribute new or existing tokens to many wallet addresses, often as part of a promotional campaign or as a reward to early adopters.
Alpha
Alpha refers to insider or early adopter information on a project, e.g., a cryptocurrency, dapp (decentralized application), or other Web3 venture.
Altcoin
An altcoin is a cryptocurrency token/coin other than Bitcoin and is referred to as an “alternative coin” or “altcoin.” The term “altcoin” comes from the combination of the words “alternative” and “coin.”
AMM
An automated market maker (“AMM”) is a protocol that usually runs on a decentralized exchange. It provides automatic quotes for trades and replaces traditional buy-and-sell order liquidity with liquidity pools that anyone can use or join.
API
An application programming interface (“API”) is a set of protocols that allow computer programs to communicate, and are often used to offer services or data to other applications. In simple terms, an API is a messenger allowing two apps to talk with each other.
Arbitrum
Arbitrum is a secure Ethereum layer-2 (“L2”) network created by Offchain Labs. It’s an EVM-compatible network aiming to solve the scalability issues of Ethereum. Some of its advantages are low fees and EVM compatibility.
Moralis features Arbitrum support and provides an Arbitrum Goerli faucet for developers to use before launching on the mainnet.
Avalanche
Avalanche is a fast EVM-compatible blockchain supported by Moralis APIs. Ava Labs created the Avalanche network in 2020, and its main benefits are speed, interoperability, low fees, and eco-friendliness.
B
Bitcoin
Bitcoin is the original decentralized digital currency created by the pseudonymous developers/developer Satoshi Nakamoto. Bitcoin transactions are executed and recorded on the Bitcoin blockchain network.
Block Explorer
A block explorer is a tool that allows users to view various blockchain metrics, including hashrate, average transaction fees, addresses, and more. Most blockchain networks have their own block explorers.
Block explorers, such as Etherscan, are useful tools. For example, a developer can mint from Etherscan contracts.
Block Size
Block size indicates how much transaction data an individual block can hold. Different blockchain networks can have different size blocks.
Blockchains and Blocks
Blockchains consist of “blocks” of data and networks of nodes. Each block is a collection of transaction information, while each node holds a record of all verified transactions.
New blocks submitted to the network are verified by the nodes and either added to the blockchain as immutable data or rejected if invalid.
Block size varies depending on the blockchain. For example, the Bitcoin network block size is limited to 1 MB, whereas Ethereum blocks have no fixed size.
Each block can be identified by its own block number and hash.
BNB Chain
BNB Chain is one of the most popular programmable blockchains and smart contract platforms. BNB Chain comprises BNB Beacon Chain (formerly Binance Chain) and BNB Smart Chain (formerly Binance Smart Chain). Moralis features full support for BNB Chain.
Bridge
A bridge allows assets such as tokens or NFTs from different blockchain networks to be transferred or “bridged” between each other.
Burn
“Burning” is the process of destroying and removing tokens or NFTs from circulation. Burning is the opposite of minting.
C
CEX
CEX stands for “centralized exchange” and describes crypto exchanges operated by centralized business entities, such as Coinbase, Kraken, or Binance.
Compute Units
A compute unit is a measure of the requests needed to query computationally expensive API endpoints. Each request has both price and rate limit costs that are measured in terms of compute units.
Consensus
The protocol by which blockchains come to an agreement about transactions. All nodes in the network must achieve consensus for transactions to be processed and added to the blockchain. Proof-of-work and proof-of-stake are examples of consensus protocols.
Cronos
Cronos is an EVM-compatible blockchain that uses a proof-of-authority (PoA) consensus model. The network was launched in 2021. Since then, it has been running parallel to Crypto.org’s chain. As you might have figured out, Crypto.org (which has been around since 2016) is the organization behind Cronos.
Cronos development is becoming increasingly popular, and Moralis currently supports Cronos integration.
Cross-Chain
A feature that allows Web3 development tools to work on multiple blockchain networks and access and share data across different blockchains. Also, there is something known as “cross-chain bridging”, enabling users to transfer tokens and data between blockchains.
D
DAO
A decentralized autonomous organization (“DAO”) is a digital collective or community that operates on a blockchain network. It follows a set of rules that are programmed into and automatically executed by smart contracts.
A DAO is like a “governing body” of a Web3 project, enabling an organization to run completely democratized.
Dapp
A decentralized application (“dapp”) is any application built on a blockchain. Dapps often use smart contracts to provide functionality automatically. Dapps are also known as Web3 applications.
DeFi
Decentralized finance, commonly called DeFi, is a financial technology native to blockchains. The term comes from the fact that blockchains are not controlled by a single centralized entity (like a central bank, for example).
DeFi translates many “traditional” financial products and practices to the blockchain, including lending and borrowing.
DEX
A decentralized exchange (“DEX”) is a platform where various cryptocurrencies can be swapped, traded, and added to liquidity pools. A DEX is run by smart contracts and not controlled by a single business entity, group, or individual.
E
EIP
An Ethereum Improvement Proposal (“EIP”) is a protocol anyone can use to request or suggest improvements to the Ethereum blockchain. The Ethereum community then reviews the EIP, and if approved, the proposal is added to the network in the next available update.
Endpoint
An endpoint is one end of the API communications channel. An API endpoint lets a user interact with a specific functionality of a remote service. API endpoints can, in some cases, include the URL of a service.
You can find all the Moralis API endpoints in our Web3 documentation.
ENS Domain
ENS domains are unique and come with a “.eth” extension, following the ERC-721 standard. Ethereum Name Service (“ENS”) is an extensible, distributed, open Ethereum-based naming service. ENS’ purpose is to map human-readable names (e.g., “adam.eth”) to machine-readable identifiers like Web3 wallets.
Epoch
An epoch is a unit of time on a blockchain, generally measured in the time it takes for the network to process a certain number of blocks.
An epoch on the Ethereum network is the amount of time it takes to process 30,000 blocks, for example.
ERC
ERC stands for “Ethereum Request for Comment.” An ERC is derived from an Ethereum Improvement Proposal (EIP).
ERCs describe standards for the Ethereum platform, including core protocol specifications, client APIs, and contract standards. Network upgrades are discussed separately in the Ethereum project management repository.
The most popular ERC standards are ERC-20 and ERC-721.
Ethereum
Ethereum is an open-source, decentralized, smart contract-enabled blockchain network. It was launched in 2015 by Vitalik Buterin. Ethereum’s native cryptocurrency is called ETH (ether), which is used to pay for transactions and services on the Ethereum mainnet. Additionally, developers can create other crypto assets on top of the Ethereum blockchain following various ERC standards.
Many layer-2 (“L2”) networks are built on top of – or are compatible with – the Ethereum network.
Events
Events are EVM logs. Events are inheritable members of contracts. When you call them, they cause arguments to be stored in transaction logs – a unique data structure in the blockchain. These logs are associated with the contract’s address, are incorporated into the blockchain, and stay there as long as a block is accessible.
A log and its event data are not accessible from within contracts (not even from the contract that created them). Source: Solidity docs.
EVM
Ethereum Virtual Machine, (“EVM”), is the engine in which transaction code gets executed. EVM enables the development of thousands of different applications on one platform.
Smart contracts written in smart contract-specific programming languages are compiled into “bytecode,” which EVM can read and execute.
Exchange
A general term for either a centralized exchange or decentralized crypto exchange.
F
Fantom
The Fantom network is a fast and scalable blockchain, home to DeFi and Web3 enterprise applications and fully integrated with the enterprise blockchain solutions from Moralis.
Fantom is one of the most popular blockchains with EVM compatibility. Its mainnet is called “Fanom Opera,” which is built on Lachesis – the consensus mechanism from Fantom. Some of Fantom’s advantages include fast transaction speeds, deterministic finality, and low transaction costs.
Faucet
A crypto faucet is a website or app that provides users with small amounts of testnet cryptocurrency, often for completing simple tasks such as executing transactions on a testnet. It’s commonly used to introduce new users to cryptocurrency and blockchain technology or by developers to test new dapps.
Here are some examples of available testnet faucets:
Fiat
Fiat currencies are currencies issued by governments or states that are not backed by commodities, such as gold or other precious metals. They are instead backed by faith and trust in the issuing government.
Fork
A fork occurs when a blockchain splits into two different branches. There can be many reasons for a fork (usually upgrades), and the community usually votes on the decision to fork a network. Forked networks preserve their transaction history up until the date of the fork.
Fungible Token
A fungible token represents an asset or equity that can be traded with another token or digital asset. Tokens on the blockchain are immutable, meaning they have a fixed name, symbol, and total supply, unless or otherwise made mutable with the help of a smart contract.
The ERC-20 standard is the most popular option for deploying a token on EVM chains.
G
Gas
Gas is the cost of completing a transaction on a blockchain network. On Ethereum, for example, gas transaction costs are a small fraction of Ethereum’s native token, ETH.
Genesis Block
The first ever block created on a blockchain.
Geth
Geth, or go-Ethereum, is the Go implementation of Ethereum. Go is an open-source programming language.
Gwei
A gwei is one billionth of an ETH, the native token of the Ethereum blockchain.
Want to convert gwei to ETH? Use our gwei to ETH calculator.
H
Hard Fork
A hard fork occurs when a blockchain network splits into separate branches due to upgrades or other changes. Hard forks are backward incompatible, meaning that the two separate networks cannot be reconciled once the hard fork occurs.
Hashrate
A blockchain’s hashrate is the measure of the computational power on the network in terms of calculations per second.
I
IPFS
The InterPlanetary File System (“IPFS”) is a distributed system for storing and accessing files, websites, applications, and data. For example, developers can use IPFS with Ethereum for their IPFS NFT projects.
L
Layer-1 (L1)
A layer-1 (L1) blockchain (a.k.a. “mainnet”) is the base level of a blockchain. Ethereum and Bitcoin are examples of layer-1 blockchains.
Layer-2 (L2)
Layer-2 (L2) refers to a secondary framework or protocol built on top of an existing layer-1 blockchain. L2s are usually scaling solutions.
Layer-2 blockchains typically improve transaction speeds and cost efficiency. As layer-2 protocols continue to scale, mempool data gives builders looking to migrate or build dapps the tools to create the best user experiences.
Light Client
A light client is a blockchain client that does not store the entire blockchain. Instead, the light client relies on other nodes in the network to provide the necessary information. This allows for a more lightweight way of interacting with a blockchain network.
Liquidity Pool
A liquidity pool is a pool of cryptocurrencies available to trade on a decentralized exchange (DEX). Pools are usually composed of assets deposited by users, which can be traded with other assets in the pool through smart contracts.
Liquidity
Liquidity is the ease with which one token or digital asset can be converted to another.
M
Mainnet
A mainnet is the production version of a blockchain network where transactions and other operations are recorded and processed. It is a blockchain protocol’s primary and original network, as opposed to a testnet.
Mining
Mining is the process of using specialized computer hardware to perform complex mathematical calculations to validate and record transactions on a blockchain network in return for cryptocurrency. Mining is usually carried out by validators or miners.
Mint
To “mint” refers to the process of creating new units of a specific digital token, either coins or NFTs. There are numerous ways minting can occur. For example, a developer can mint an NFT on a marketplace such as OpenSea or mint an NFT from a contract.
N
NFT
A non-fungible token (“NFT”) is a unique digital token stored on the blockchain. An NFT differs from ETH, BTC, or other fungible tokens, as each NFT is one-of-a-kind and cannot be replicated. Furthermore, NFTs can be used to digitally represent individual assets, most commonly art, real estate, tickets, and rare collectibles. They can also be used as a “digital passport,” allowing users to access gated communities, events, or websites.
NFT metadata describes an NFT’s essential properties, including name, transaction history, total supply, etc.
The ERC-721 standard is often used to create NFTs on EVM-compatible blockchain networks. Ever since the launch of NFTs, NFT development has become pretty popular. With the Moralis NFT API, developers can fetch real-time NFT metadata, transfer and ownership data, NFT prices, and much more!
Nonce
In cryptocurrency mining, a nonce is a number added to a block header to produce a hash that meets a specific difficulty target and allows the block to be added to the blockchain.
O
Optimism
The Optimism network is a layer-2 scaling solution for Ethereum, which uses “optimistic rollup” technology to allow faster and cheaper transactions off-chain, while still being secured by the underlying Ethereum blockchain.
P
P2E
Play-to-earn (“P2E”) games allow players to acquire in-game assets, items, or currencies. These assets can be used in other games or sold on secondary markets for real money.
Palm
The Palm blockchain network provides a low-cost, high-performance infrastructure for dapps. It uses a new consensus algorithm called “proof-of-stake and trust” that combines proof-of-stake security with the scalability and decentralization of sharding.
PFP
An NFT used as a profile picture (PFP). Popular NFT PFPs include Bored Apes and Crypto Punks.
Polygon
The Polygon network is a layer-2 scaling solution for Ethereum that uses a system of interconnected Ethereum sidechains to facilitate faster, cheaper transactions and lower gas fees.
Post-State
Post-state refers to the state of a smart contract on the blockchain after it has been executed. Post-state includes the final values of all variables and the status of the contract, including any changes made to the blockchain due to the contract’s execution.
Private Key
A private key, or seed phrase, is a secret code that allows the owner to access and manage their crypto assets on the blockchain via a crypto wallet like MetaMask. It is used to sign transactions and provide proof of ownership. Your private key should never be shared with anyone.
Proof-of-Authority
Proof-of-authority (“PoA”) is a consensus mechanism where the nodes that validate transactions and create new blocks are chosen based on their identity, typically by a central authority.
Proof-of-History
Proof-of-history (“PoH”) is a consensus mechanism that allows a blockchain to efficiently verify the inclusion of historical data without requiring each node to store all historical data. It uses a combination of hash chains and Merkle trees to prove that no one has tampered with the data.
Proof-of-Stake
Proof-of-stake (“PoS”) is a blockchain consensus mechanism that achieves consensus by choosing the next validator using various combinations of random selection, including how many coins validators have “staked” or “locked” in the network.
Proof-of-Work
Proof-of-work (“PoW”) is a consensus mechanism by which a blockchain network achieves distributed consensus by choosing the next block producer (miner) via a computational race. The miner who solves a cryptographic puzzle the fastest gets to add the next block to the chain and is rewarded for their work in cryptocurrency.
Public Key
A public key is a cryptographic key used to encrypt data and verify digital signatures. It can be shared publicly and is combined with a private key to encrypt and decrypt messages and digital signatures.
R
Records
Records are the data retrieved by the Moralis Streams API webhook and count toward stream usage and limits. Records can be transactions, logs, or internal transactions.
RPC Node
RPC nodes, or remote procedure call nodes, are responsible for storing and propagating transactions in the network. They are servers that provide public access points to blockchain networks and are used by dapps to interact with and read data from blockchains via APIs (such as the APIs from Moralis).
As shown in the image below, node A broadcasts a transaction to node B and node C in the network. The nodes (A, B, and C) then verify this transaction before forwarding it to their peers, and so on.
Self-hosting RPC nodes exist but require extensive infrastructure, support, and management. Moralis APIs remove the need to self-host an RPC node.
S
Satoshi
A “satoshi” is a small fraction of a Bitcoin. Specifically, one satoshi is equivalent to 100 millionth of a Bitcoin and is named after Satoshi Nakamoto, Bitcoin’s enigmatic creator.
Seed Phrase
A seed phrase is a collection of random words that form a sequence required to unlock and access cryptocurrency wallets. The seed phrase can be used to recover a wallet on any device. Your seed phrase should be protected and never shared.
Sharding
Sharding is a process that organizes a blockchain network into multiple smaller “pieces” or smaller networks.
Signing
“Signing” in Web3 is the process of creating a digital signature using a combination of your wallet’s private keys, cryptography, and encryption.
When you sign anything using your wallet, the receiving address (or “signee”) decrypts and verifies that the request was sent by your private key and completes the transaction.
Smart Contract
A smart contract is also called a “Web3 contract.” A smart contract is a computerized transaction protocol that executes the terms of a contract. Furthermore, it automatically executes on the blockchain when specific conditions of the initial contract/agreement are met. Also, smart contracts remove the need for mediators or middlemen.
Solana
Solana was launched in 2017 by Anatoly Yakovenko and Raj Gokal. Furthermore, Solana is a public, open-source, decentralized blockchain built to enable scalable, user-friendly dapps. It supports smart contracts and the development of fungible and non-fungible tokens and dapps.
Solana’s native cryptocurrency is called “SOL,” which provides network security and serves as a means to transfer value on the network.
Solidity
Solidity is one of the most popular Web3 programming languages created especially for the Ethereum network. It is an object-oriented programming language designed to create smart contracts.
SPL Token
The Solana Program Library (“SPL”) is equivalent to ERC on Ethereum, but for the Solana blockchain.
The SPL token is the standard used to issue tokens on the Solana blockchain, similar to the ERC-20 standard used to issue tokens on Ethereum.
Staking
Staking means “locking up” tokens on a blockchain network to be used as part of the proof-of-stake (PoS) consensus model. In return for helping secure the network and process transactions, staked tokens generate rewards over time as a percentage of the total amount locked up.
Stale Block
Stale blocks are blocks that have been mined but not added to the network because a block of the same size was added to the network first or mined faster.
Stream
A “stream” is a real-time collection of customizable blockchain data gathered from on-chain events by the Moralis Streams API webhook. This data could be when a new event is emitted in your contract or when a wallet address executes an NFT transfer. Also, with the Moralis Streams API, you can set up Web3 notifications and crypto wallet tracking.
T
Testnet
A testnet is a test version of a blockchain network used for testing and development purposes. It allows developers to experiment with and test dapps without using real assets.
Throughput
Throughput is the number of units of information that can be processed in a given amount of time. Moralis measures throughput in compute units (CU).
Token
A token is a digital asset representing a specific use case or value within a decentralized platform or ecosystem. Tokens can represent ownership of a particular asset, access to a service, or be used as a means of exchange within a community.
TPS
Transactions per second (“TPS”) defines the number of transactions a blockchain network can process per second. Higher TPS means a network can process more transactions per second, making higher TPS blockchains the increasingly preferred option for developers.
Transaction
A transaction on a blockchain is the action of buying, selling, swapping, or trading a cryptocurrency or NFT. For example, it can mean sending an NFT from one address to another, either on the same network or across different chains (provided both networks support cross-chain transactions).
TVL
Total value locked (“TVL”) is the measurement of the total amount of assets locked in smart contracts on a blockchain network. TVL is generally used to assess the popularity of a DeFi protocol or ecosystem.
Type 0 Transaction
Type 0 transactions are no longer used. They are legacy transactions previous to the Ethereum London hard fork that occurred in August 2021, which included the deployment of EIP-1559.
Type 2 Transaction
Type 2 transactions are based on the EIP-1559 upgrades and include the base fee, max priority fee, and max fee per gas field instead of the gas price field. Blocknative’s Gas Platform API and Gas Estimator support type 2 and type 0 transactions.
U
Unstoppable Domain
Similar to ENS, Unstoppable Domains is a company that provides human-readable names as NFTs, which are linked to specific wallet addresses. They follow the ERC-721 standard and come with various extensions such as “.crypto,” “.nft,” and “.blockchain.”
V
Validator
A validator participates in a blockchain network and validates and adds new transactions. Validators use consensus algorithms to agree on the blockchain’s state and maintain its integrity.
W
Wallet
A cryptocurrency wallet is a device or program that stores your cryptocurrency keys and allows you to access your tokens. Your wallet is the Web3 equivalent of your bank account.
Each wallet can have multiple addresses attached to it. A wallet address is similar to an account number in traditional banking.
Your wallet is accessed using a private cryptocurrency key, also called a seed phrase. This is the same as a master password or digital login that you might have for an online bank, with one crucial difference: anyone who has your private key can access and sign transactions. Moreover, anyone with access to your private keys can access your funds, which can result in you losing your assets permanently. Therefore, never share your private keys.
MetaMask is one of the most popular and comprehensive Web3 wallets: https://metamask.io/.
Web3
Web3 is the next generation of the internet, built on decentralized technologies such as blockchain, allowing decentralized applications and peer-to-peer transactions to take place without intermediaries. Web3 technology empowers individuals by giving them control over their data and assets.
Whale
A whale is an individual or organization that holds a large amount of cryptocurrency. Whales often significantly influence the market due to their ability to buy or sell large amounts of cryptocurrency at once, potentially causing large price movements.
Whitelist
A whitelist is a list of pre-approved individuals or entities allowed to participate in an exclusive early access activity, such as an initial coin offering (“ICO”) or token sale.