> For the complete documentation index, see [llms.txt](https://docs.cloudassert.com/wap-billing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cloudassert.com/wap-billing/master.md).

# Introduction

Usage and Billing for Windows Azure Pack has four components. All of these can be installed from their respective installers:

1. API Service – IIS Web Application
2. Aggregation Service – Windows Service
3. Admin Extension – Windows Azure Pack Admin Portal Extensions
4. Tenant Extension – Windows Azure Pack Tenant Portal Extensions

These components can be installed on the same machine or multiple machines.