> For the complete documentation index, see [llms.txt](https://arch-ecs.gitbook.io/arch/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://arch-ecs.gitbook.io/arch/documentation/world.md). # World The **world stores all its** [**entities**](/arch/documentation/entity.md), it contains methods to create, destroy and query them and handles all the internal mechanics. Therefore it is the most important class, you will use the world heavily. Time to play God. ## Lifecycle ```csharp var world = World.Create(); // Creating a world full of life world.TrimExcess(); // Frees unused memory world.Dispose(); // Clearing the world like God in the First Testament World.Destroy(world); // Doomsday ``` {% hint style="info" %} Multiple worlds can be used in parallel, each instance and its entities are completely encapsulated from other worlds {% endhint %} Best of all, you can create any number of worlds with almost infinite entities. You rarely have so much life and freedom. To be precise,`2,147,483,647` worlds with `2,147,483,647` entities each are possible. ## Customize You can also customize the world a little to suit your needs, for example the initial capacity or how big the [`chunks`](/arch/documentation/archetypes-and-chunks.md) should be:

var customizedWorld = World.Create(
    chunkSizeInBytes: 16_382,              // The base size of each chunk
    minimumAmountOfEntitiesPerChunk: 100,  // The base amount of entities per chunk
    archetypeCapacity: 8,                  // The initial size of the archetype array
    entityCapacity: 64                     // The initial amount of entities
);

{% hint style="info" %} Adjusting this is not absolutely necessary, but can be quite helpful. These are always initial values that Arch uses as a guide. It may well be that Arch deviates upwards in some cases, especially with the `chunkSizeInBytes` or the `minimumAmountOfEntitiesPerChunk`. {% endhint %} ## Good to know Now we have a world. A world with all the prerequisites for creating life, changing it and destroying it. The world has the rudimentary methods on which everything in Arch is based. If you only want to work with them, this is possible and offers one less level of abstraction. {% hint style="info" %} As an alternative, you can also work ONLY with the world. Without abstraction of entities and co. This principle is called [`PURE_ECS`](/arch/documentation/optimizations/pure_ecs.md) and will be looked at later. The following documentation refers further to the abstracted entity API. {% endhint %}


Lifecycle Management	Creating and destroying Entities.	/pages/j0ftYP0tbdyGFrK7jqgr
Structural Changes	Adding/Removing components on Entities	/pages/j0ftYP0tbdyGFrK7jqgr
Modification	Accessing and modifying components on Entities.	/pages/j0ftYP0tbdyGFrK7jqgr
Enumeration	Enumerating/Filtering/Matching Entities.	/pages/5xPAMh2HX8LbmzbCsWCy
Bulk/Batch Operations	Executing operations on Entities in Bulk/Batches.	/pages/IMO9t00WfXAoKg260Wec
Lowlevel	Working with Archetypes, Chunks and Entities directly without any wrappers.	/pages/ZfoFJytBxbDGZXOjnJwH
Multithreading	Acessing the JobScheduler to run querys or your own Jobs in parallel.	/pages/JcSCnW1i5lZENg1XHcqe
And much more...	Working with Events, the CommandBuffer or several other features directly!

We'll go into more detail later. But now enough talk, go on. Something is lurking behind the next bush. --- # 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://arch-ecs.gitbook.io/arch/documentation/world.md?ask=&goal= ``` `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.