An SPL program (MemoSq4gqABAXKb96qnH8TysNcWxMyWCqXgDLGmfcHr) that validates a UTF-8 string and records it in the transaction log. Memos attach human-readable notes to transactions—used for exchange deposit identification, compliance metadata, and transaction tagging. The memo must be signed by at least one account.
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An SPL program (MemoSq4gqABAXKb96qnH8TysNcWxMyWCqXgDLGmfcHr) that validates a UTF-8 string and records it in the transaction log. Memos attach human-readable notes to transactions—used for exchange deposit identification, compliance metadata, and transaction tagging. The memo must be signed by at least one account.
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SPL assets, token standards, metadata, and NFT primitives.
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Memo Program (memo-program) Category: Token Ecosystem Definition: An SPL program (MemoSq4gqABAXKb96qnH8TysNcWxMyWCqXgDLGmfcHr) that validates a UTF-8 string and records it in the transaction log. Memos attach human-readable notes to transactions—used for exchange deposit identification, compliance metadata, and transaction tagging. The memo must be signed by at least one account. Related: Solana Program Library (SPL), Transaction
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Solana Program Library—a collection of on-chain programs and client libraries maintained by Solana Labs. Key SPL programs include Token, Token-2022, Associated Token Account, Memo, Name Service, Stake Pool, and Account Compression. SPL programs are deployed to well-known addresses and serve as the standard building blocks for Solana applications.
An atomic unit of execution containing one or more instructions, a recent blockhash, and one or more signatures. All instructions in a transaction execute sequentially and atomically—if any instruction fails, the entire transaction reverts. Transactions have a 1,232-byte size limit (matching IPv6 MTU) and a default 200,000 CU budget.
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A Token-2022 extension that requires all incoming transfers to include a memo instruction (via the Memo Program) in the same transaction. If no memo is present, the transfer fails. Used for compliance-driven tokens where transaction metadata must be recorded on-chain.
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Solana Program Library—a collection of on-chain programs and client libraries maintained by Solana Labs. Key SPL programs include Token, Token-2022, Associated Token Account, Memo, Name Service, Stake Pool, and Account Compression. SPL programs are deployed to well-known addresses and serve as the standard building blocks for Solana applications.
An atomic unit of execution containing one or more instructions, a recent blockhash, and one or more signatures. All instructions in a transaction execute sequentially and atomically—if any instruction fails, the entire transaction reverts. Transactions have a 1,232-byte size limit (matching IPv6 MTU) and a default 200,000 CU budget.
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The original Solana Program Library token program (TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA) that implements fungible and non-fungible token operations. It manages mints (token definitions) and token accounts (balances). Core instructions include InitializeMint, MintTo, Transfer, Burn, Approve (delegation), and Revoke. All SPL tokens on mainnet before Token-2022 use this program.
Solana Program Library—a collection of on-chain programs and client libraries maintained by Solana Labs. Key SPL programs include Token, Token-2022, Associated Token Account, Memo, Name Service, Stake Pool, and Account Compression. SPL programs are deployed to well-known addresses and serve as the standard building blocks for Solana applications.
The next-generation token program (TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb) that extends SPL Token with configurable extensions. Extensions include transfer fees, confidential transfers, transfer hooks, permanent delegate, non-transferable tokens, interest-bearing tokens, metadata, and more. Token-2022 is backwards-compatible with SPL Token for basic operations.
An on-chain account defining a token type. A mint specifies: supply (total minted), decimals (0 for NFTs, 6 for USDC, 9 for most tokens), mint authority (who can mint), and optional freeze authority. Each unique token (USDC, JitoSOL, etc.) has exactly one mint account. Mint address serves as the token's unique identifier.