> For the complete documentation index, see [llms.txt](https://docs.arkannis.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.arkannis.net/cloud/azure/courses/az900-course/cloud-models-and-cloud-types/iaas-paas-saas.md).

# IaaS, PaaS, SaaS

## "Something" as a Service

* The idea is that you don't own that thing
* Someone lese owns it and you benefit from it - "as a service"
* You're not in control of how it's delivered (for the most part)
* Pay as you go; no upfront costs

**Example**: Cooking at home --> Cooking as a Service (Restaurant) Driving your own car --> Driving as a Service (Taxi)

## Software as a Service (SaaS)

* You `don't control` the servers (or even know what they are)
* You `don't control` the software (or even know what version number is running)
* You `control` the data and settings only

**It stands alone as a useful product; does not require something else to be useful**

**Example**: Microsoft Office 365 - SaaS Sharepoint, Outlook, Word, Excel, etc...

## Platform as a Service (PaaS)

* You `don't control` the servers (but you might be able to pay more for performance)
* You `control` the data and settings
* Often it's programmable and you can upload your own code
* Provides useful features above the raw storage or compute underneath

**It's a platform that you need to build upon to be useful**

**Example**: App Service - PaaS Azure SQL Database - PaaS

## Infrastructure as a Service (IaaS)

* You `do control` the VM
* It's a virtual imitation of a real piece of a network
* Falls into 3 categories:
  * Compute
  * Networking
  * Storage

**Completely "dumb" unless you control it**

**Example**: Virtual Machines - IaaS Azure Storage - IaaS Load Balancer - IaaS

***


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.arkannis.net/cloud/azure/courses/az900-course/cloud-models-and-cloud-types/iaas-paas-saas.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.