Crypto Meta-Formats Explained

TL;DR

Yes, there are several meta-formats used with cryptocurrency to add extra information or functionality beyond just sending coins. These include token standards (like ERC-20 for Ethereum), data formats like JSON and CBOR, and protocols like Ordinals for Bitcoin NFTs. This guide explains the main ones and how they’re used.

What are Crypto Meta-Formats?

When we talk about ‘meta-formats’ in crypto, we mean ways of structuring data *around* a cryptocurrency transaction or token. It’s not just about sending Bitcoin from one wallet to another; it’s about adding extra layers of meaning and capability.

1. Token Standards

These are the most common meta-formats, especially on blockchains that support smart contracts (like Ethereum). They define a standard set of functions and data fields for tokens. This makes them interchangeable – different wallets and exchanges can all understand how they work.

• ERC-20: The standard for fungible tokens (think currencies or reward points) on Ethereum. It defines functions like transfer, balanceOf, and approve.
• ERC-721: For non-fungible tokens (NFTs). Each token is unique. Functions include ownerOf, safeTransferFrom, and tokenURI (which points to metadata about the NFT).
• ERC-1155: A more efficient standard that can handle both fungible *and* non-fungible tokens in a single contract.

You don’t usually interact with these standards directly; your wallet or dApp (decentralised application) handles it for you.

2. Data Formats

These are ways of encoding information that’s included in transactions or stored alongside tokens.

• JSON (JavaScript Object Notation): A human-readable text format. Often used to store metadata about NFTs, like the name, description, and image URL.
• CBOR (Concise Binary Object Representation): A more compact binary format than JSON. Useful for reducing transaction sizes, especially on blockchains with high fees. Example:

  # Example CBOR encoded data (simplified)

• Protobuf (Protocol Buffers): Another binary format developed by Google. Similar to CBOR in terms of efficiency.

3. Bitcoin Specific Formats

Bitcoin’s scripting language is limited, but clever people have found ways to add meta-data.

• Ordinals: A protocol that allows you to ‘inscribe’ data onto individual satoshis (the smallest unit of Bitcoin). This is how Bitcoin NFTs are created. The data is stored directly in the transaction itself, using Taproot and Script.
• Colored Coins: An older method where small amounts of Bitcoin were used to represent other assets or tokens. Less popular now due to limitations.

4. How to Check Meta-Data

How you check the meta-data depends on the crypto and format.

• Ethereum Tokens: Use a block explorer like Etherscan (https://etherscan.io). Search for the token contract address, then look at the ‘Contract’ tab to see its functions and data fields.
• NFT Metadata (ERC-721): Use a block explorer or NFT marketplace. The tokenURI field in the ERC-721 standard will point you to where the metadata is stored (often on IPFS).
• Bitcoin Ordinals: Use an Ordinals explorer (https://ordinals.com) or a Bitcoin block explorer that supports Ordinals. You’ll need the transaction ID to find the inscription data.

5. Security Considerations

• Metadata Storage: If metadata is stored off-chain (e.g., on IPFS), ensure it’s reliably pinned and accessible. Losing the metadata means losing information about your NFT.
• Smart Contract Audits: For tokens, always check that the smart contract has been audited by a reputable firm to identify potential vulnerabilities.
• Ordinals & Transaction Fees: Inscribing data onto Bitcoin can be expensive due to transaction fees.