# Glossary | Term | Meaning | | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | EVM | Ethereum Virtual Machine | | DeFi | Decentralized Finance | | DB | Database | | rdPoS | Random Deterministic Proof-of-Stake | | RLP | Recursive-Length Prefix | | BDK | Blockchain Development Kit | | NFT | Non-Fungible Token | | RPC | Remote Procedure Call | | UTXO | Unspent Transaction Output (commonly used by Bitcoin-derived chains, analogous to Accounts, used by Ethereum-derived chains) | | Secp256k1 | The elliptic curve used for Bitcoin’s public key cryptography | | Token table | A record of the token balances on each subnet, held by AppLayerLabs | | Block race condition | A situation where multiple blocks compete for the position of the next block in the chain | | Block congestion system | A component that manages the registration of blocks in the blockchain | | RNG | Random Number Generator, a component in charge of making validator selection unpredictable | | Master address | The address that adds validators to the network in a centralized implementation | | Transpiler | A program that converts source code written in a specific programming language into its equivalent in another language | | Constructor | A function that initializes the state variables of a contract | | Pointer | An item that shows where data is stored and helps verify it | | Sandbox | An isolated testing environment for experimenting with code | | Merkle tree | An abstract data type with leaves (nodes) holding cryptographic hashes of data blocks while nodes that aren’t leaves have cryptographic hashes of their child nodes | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.applayer.com/testnet/glossary.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.