Created Instances (markdown)

Instances.md

@@ -0,0 +1,26 @@
+Instances are what replace "world" from Minecraft vanilla, those are lightweight and should offer similar properties
+
+They can be accessed by using the InstanceManager or by getting an entity instance
+```java
+InstanceManager instanceManager = MinecraftServer.getInstanceManager()
+// Or
+Entity#getInstance
+```
+
+There are two kinds of instance: InstanceContainer and SharedInstance
+
+An InstanceContainer contains both chunks and entities, a SharedInstance needs to share chunks with its container.
+
+You can create an InstanceContainer by calling:
+```java
+InstanceContainer instanceContainer = instanceManager.createInstanceContainer();
+```
+And a SharedInstance using:
+```java
+SharedInstance sharedInstance = instanceManager.createSharedInstance(instanceContainer);
+```
+
+Instances do need to have a ChunkGenerator specified, without it no chunk can be generated.
+```java
+instance.setChunkGenerator(YOUR_GENERATOR);
+```