> For the complete documentation index, see [llms.txt](https://v1.docs.blueberry.garden/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://v1.docs.blueberry.garden/developer-guides/contracts/blueberry-bank/introduction.md).

# Introduction

These are the main contracts of Blueberry, responsible for being a record of storage, setting fees, and deployments. 

[BlueberryBank.sol](/developer-guides/contracts/blueberry-bank/blueberry-bank-contract.md) is the main contract that users interact with. It is important as it stores the user's positions and tracks the borrowing of tokens. 

* [Fee Manager](/developer-guides/contracts/blueberry-bank/fee-manager.md): Defines the types of fees taken in the protocol.
* [ProtocolConfig](/developer-guides/contracts/blueberry-bank/protocolconfig.md): Defines all configurable states of the protocol.