> For the complete documentation index, see [llms.txt](https://docs-v4.nftx.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs-v4.nftx.io/getting-started/introduction.md).

# Introduction

NFTX v4 is a **neutral fungibility layer for NFTs**: it turns NFT collections into liquid, fungible markets. Depositing an NFT into a collection's vault mints a fungible **floor token** (an ERC‑20, also called a vault token) that's backed 1:1 by the pool and redeemable for any floor NFT in that vault — so NFTs can be traded, pooled, and priced like any token. It's a relaunch on **Uniswap V4**, keeping fungible floor liquidity and adding a self-assessed listing system for non-floor items.

This section gets you oriented. From here, [How It Works](/how-it-works/floor-tokens.md) walks through the protocol in plain language — floor tokens, Liquid Listings, swaps, and the collection lifecycle. The deeper [Core Concepts](/core-concepts/vaults.md) cover the mechanics, the on-chain [Contracts](/contracts/contracts.md) are the reference, and the [API Reference](/api-reference/api-reference.md) is for integrators.