# Understanding Souls and SBTs ## Souls Souls represent unique smart contracts, acting as a digital passport for each user on the Cardano blockchain. Every Soul is intrinsically linked to the user's wallet at creation, representing the user's unique identity within the ecosystem. Due to the specific design, Souls are immutable and non-transferrable, thereby maintaining each user's distinct identity. ## Soulbound Tokens (SBTs) SBTs are essentially Non-Fungible Tokens (NFTs) with a twist. While NFTs are unique and transferable between users, SBTs are 'soulbound,' meaning they are permanently tied to the user's Soul. The soulbound feature of these tokens is not inherent in the tokens themselves but is instead defined by the Soul's smart contract. --- # 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://cryptoraggies.gitbook.io/welcome/soul-and-soulbound-token-sbt/whitepaper/understanding-souls-and-sbts.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.