# Internal Functionality

This section describes in detail the internal workings of each component in Espresso.

## Contracts Overview

Core Contracts:

* [`LightClient`](https://docs.espressosys.com/network/concepts/the-espresso-network/internal-functionality/light-client)
* [`FeeContract`](https://docs.espressosys.com/network/concepts/the-espresso-network/internal-functionality/fee-token)
* [`StakeTable`](https://docs.espressosys.com/network/concepts/the-espresso-network/internal-functionality/stake-table/stake-table) (not used for Mainnet 0)