Feature: Create docs for v4 introduction

content/concepts/v4-nft.md

@@ -0,0 +1,23 @@
+### What is NFT?
+
+A non-fungible token stored on the blockchain represents a unique asset. NFTs can represent images, videos, digital art, or any piece of information. NFTs can be traded and allow transfer of ownership and copyright.
+
+### How are NFTs handled in the Blockchain world?
+
+[EIP-721](https://eips.ethereum.org/EIPS/eip-721) defines an interface for handling NFTs on Ethereum blockchain. The creator of the NFT can deploy a new contract on Ethereum or any Blockchain supporting NFT related interface and also, transfer the ownership through the transaction(s).
+
+### How will Ocean Protocol support the NFT market?
+
+Ocean Protocol defines an [ERC721Factory](https://github.com/oceanprotocol/contracts/blob/v4Hardhat/contracts/ERC721Factory.sol) contract which will allow users to deploy ERC721 contract instances on any of the supported networks. The deployed contract can be associated with Metadata information which describes, also published on-chain. The [Metadata](https://github.com/oceanprotocol/contracts/blob/v4Hardhat/contracts/metadata/Metadata.sol) contract will store the information about the asset, and associated access rights defined through roles.
+
+![Image 1](images/v4-nft-1.png)
+
+Once the contract is deployed, it will be available on the Ocean Marketplace for trade.
+
+### Other References
+
+- https://en.wikipedia.org/wiki/Non-fungible_token
+- https://blog.oceanprotocol.com/nfts-ip-3-combining-erc721-erc20-b69ea659115e
+- https://blog.oceanprotocol.com/nfts-ip-2-leveraging-erc20-fungibility-bcee162290e3
+- https://blog.oceanprotocol.com/nfts-ip-1-practical-connections-of-erc721-with-intellectual-property-dc216aaf005d
+- https://blog.oceanprotocol.com/on-difficult-to-explain-fungibility-sightings-in-nfts-26bc18620f70

content/concepts/v4-roles.md

@@ -0,0 +1,20 @@
+### Roles
+
+[ERC721Template](https://github.com/oceanprotocol/contracts/blob/v4Hardhat/contracts/templates/ERC721Template.sol) contract defines following roles:
+
+- NFT Owner
+- Manager
+
+#### NFT Owner
+
+- NFT Owner is the publisher. I.e. Owner is a public address which transacted with `ERC721Factory` contract and deployed a new `ERC721` contract.
+
+- NFT Owner can assign managers while deploying the contract.
+- NFT Owner is also added to the Managers.
+- NFT Owner can add/remove Managers.
+- Clean all permissions
+
+#### Manager
+
+- A public address with a `Magner` role can update the metadata
+- Can deploy new ERC20 contract which is associtated with the `ERC721` contract.

data/sidebars/concepts.yml

@@ -25,6 +25,13 @@
     - title: Asset DDO
       link: /concepts/oeps-asset-ddo/
 
+- group: NFTs
+  items:
+    - title: Introduction
+      link: /concepts/v4-nft/
+    - title: Roles
+      link: /concepts/v4-roles/
+
 - group: Contribute
   items:
     - title: Ways to Contribute