# Billing

> Understand how Multiplayer Services bills for resource usage and charges.

The Multiplayer Services SDK uses [sessions](/mps-sdk/create-session.md) to manage groups of players.

Sessions relies internally on different combinations of Unity Gaming Services such as [Relay](/relay.md), [Distributed Authority](https://unity.com/products/distributed-authority), [Lobby](/lobby.md), [Matchmaker](/matchmaker.md) and [Cloud Code](/cloud-code.md), and thus contributes to the [billing](https://unity.com/solutions/gaming-services/pricing) of those services.