Restructuring (#39)

* Restyle light-mode WIP

* Redesign and condensation of content

* Adjust padding of sidebars

* Remove styling

* Revert to previous layout

Author: MHHukiewitz

docs/computing/custom domain/Adding a Custom Domain.md renamed to docs/VMs/Custom Domains/Adding a Custom Domain.md

@@ -1,13 +1,37 @@
-# Persistent Execution
+# Computing on Aleph.im
 
-## Introduction
+Aleph.im offers a decentralized computing framework that allows users to run
+programs on the network. This is done by creating a virtual machine (VM) that
+executes the program.
 
-The aleph.im network can run programs in two different manners:
+## Overview of VMs
 
-* [on-demand execution](on_demand.md) runs programs only when needed, saving on resources. This is great to run programs
-  that are responding to user requests or API calls and can shutdown after processing the event.
-* __persistent execution__ runs programs continuously.  These are always running and great to run programs that cannot
-  afford to stop or need to handle incoming connections such as polling data from a websocket or AMQP API.
+There are several types of VMs available on the network:
+
+- [On-demand VM](#on-demand-execution)
+- [Persistent VM](#persistent-execution)
+- [Instance VM](#instance-vms)
+
+An [On-demand VM](#on-demand-execution) is created on a [Compute Resource Node](../nodes/Compute_(CRN)/index.md)
+(CRN) and is destroyed once the program has finished executing. This is great
+for programs that are responding to user requests or API calls (using ASGI) and can shutdown
+after processing the event. They are also cheaper to run as they only require
+one tenth of the $ALEPH tokens to hold, compared to a [Persistent VM](#persistent-execution).
+
+A [Persistent VM](#persistent-execution) can be used to run programs that cannot afford to stop or need
+to handle incoming connections such as polling data from a websocket or AMQP API.
+
+Instances are similar to Persistent VMs, but are specifically designed to run with
+a SSH key supplied by the user. This allows the user to connect to the VM and
+interact with it directly. They do not rely on code execution, but rather on
+the user's ability to connect to the VM and run commands on it.
+They cost as much as Persistent VMs.
+
+## On-demand Execution
+
+On how to deploy a simple Python microVM, see our [Python microVM guide](../guides/python/getting_started.md)
+
+## Persistent Execution
 
 When a program is created with persistent execution enabled, the aleph.im scheduler will find a Compute Resource Node
 (CRN) with enough resources to run the program and schedule the program to start on that node.
@@ -17,7 +41,7 @@ CRN would the current one go offline.
 
 > ⚠️ Automatic data migration across hosts in case such events happen is not available yet.
 
-## Message Specification
+### Message Specification
 
 The execution model of a program is defined in the field `message.content.on` of messages of type `PROGRAM` and is 
 non exclusive. The same program can therefore be available as both persistent instance and on demand at the same time.
@@ -39,7 +63,7 @@ message = {
 }
 ```
 
-## Prerequisites
+### Prerequisites
 
 Before you begin this tutorial, ensure that you have the following:
 
@@ -73,7 +97,7 @@ cd ./src/
 uvicorn main:app --reload
 ```
 
-## Step 2: Run a program in a persistent manner
+### Step 2: Run a program in a persistent manner
 
 To run the program in a persistent manner on the aleph.im network, use: 
 
@@ -87,10 +111,10 @@ You can stop the execution of the program using:
 aleph unpersist $MESSAGE_ID
 ```
 
-## Find your program
+### Find your program
 
 TODO: Locate the CRN where your program is running.
 
-## Conclusion
+## Instance VMs
 
-In this tutorial, you learned how to create and deploy persistent Virtual Machines on the aleph.im network. You should now have a better understanding of how to use aleph.im for distributed computing.
+TODO: Document Instance VMs

docs/computing/persistent.md renamed to docs/VMs/index.md

@@ -9,7 +9,7 @@ This runtime is built with software available in the distribution, including Pyt
 
 To optimize performance, this runtime uses a custom [Linux init](https://en.wikipedia.org/wiki/Init) process. This
 process is specially designed to quickly launch the right endpoint in response to events such as HTTP requests. This is
-especially useful when using [on-demand execution](../on_demand.md).
+especially useful when using [on-demand execution](../index.md#on-demand-execution).
 
 [//]: # (Not available yet)
 

docs/computing/runtimes/custom.md renamed to docs/VMs/runtimes/custom.md

@@ -14,7 +14,7 @@ custom runtimes, and use any available runtime on the network for your program.
 
 ## Init process
 
-[On-demand Execution](../on_demand.md) relies on a custom [Linux init](https://en.wikipedia.org/wiki/Init) process,
+[On-demand Execution](../index.md#on-demand-execution) relies on a custom [Linux init](https://en.wikipedia.org/wiki/Init) process,
 optimized to launch the right endpoint in response to events such as HTTP requests. This custom init consists in two
 simple programs, 
 [init0.sh](https://raw.githubusercontent.com/aleph-im/aleph-vm/main/runtimes/aleph-alpine-3.13-python/init0.sh) 
@@ -23,6 +23,6 @@ and [init1.py](https://raw.githubusercontent.com/aleph-im/aleph-vm/main/runtimes
 Use these in your custom runtime by copying them to `/rootfs/sbin/init` and 
 `/mnt/rootfs/root/init1.py` respectively.
 
-[Persistent Execution](../persistent.md) may use the same init process, but this is not required. If you do not make use
+[Persistent Execution](../index.md#persistent-execution) may use the same init process, but this is not required. If you do not make use
 of the capabilities provided by the aleph.im ecosystem, using the default of your distribution 
 (ex: [systemd](https://systemd.io/), [OpenRC](https://github.com/OpenRC/openrc), ...) should work as well.

docs/computing/runtimes/existing.md renamed to docs/VMs/runtimes/existing.md

@@ -2,7 +2,7 @@
 
 An immutable volume is a file containing
 a [Squashfs filesystem](https://www.kernel.org/doc/html/latest/filesystems/squashfs.html) that can be mounted read-only
-inside the virtual machine running programs in [on-demand](../on_demand.md) or [persistent](../persistent.md) execution
+inside the virtual machine running programs in [on-demand](../index.md#on-demand-execution) or [persistent](../index.md#persistent-execution) execution
 modes. This type of volume is typically used to provide additional libraries or data to the program.
 
 Immutable volumes have the following properties:

docs/computing/runtimes/index.md renamed to docs/VMs/runtimes/index.md

@@ -1,7 +1,7 @@
 ## Persistent Volumes
 
 Persistent volumes are logical block disks that are attached to virtual machines running programs
-in [on-demand](../on_demand.md) or [persistent](../persistent.md) execution modes. They are typically used to store
+in [on-demand](../index.md#on-demand-execution) or [persistent](../index.md#persistent-execution) execution modes. They are typically used to store
 mutable data such as databases and persist data. Currently, persistent volumes are only stored on
 the [Compute Resource Node](../../nodes/Compute_(CRN)/index.md) (CRN) that is executing the program. Automatic backups and restoration
 in case of failure of the CRN is a feature that is planned to be added in the future, and is currently left to the user.