---
title: USD
framework: USD
role: collection
role_heading: Universal Scene Description (OpenUSD)
path: usd
---

# USD

An efficient and scalable way to represent 3D scenes.

## Overview

Overview Universal Scene Description (OpenUSD, though commonly referred to as USD) is an efficient, scalable system for authoring, reading, and streaming graphics data. Originally developed by Pixar for their feature films, it is now a proposed open standard being promoted by the Alliance for OpenUSD (AOUSD). Apple and Pixar are both founding members of the AOUSD. USD is also Apple’s format of choice for 3D Content, including 3D content used for Augmented Reality. You can load USD files in your RealityKit and ARKit apps or import them into your Reality Composer Pro projects. You can even embed USD content in your apps or on web sites using AR Quick Look. USD is also an extensible format, allowing apps that use it to create custom schemas to store and load data needed to support custom features. For an example, see the proposed OpenUSD schemas for AR that Apple created, in conjunction with Pixar, to extend USD to support AR functionality like anchoring. Unlike other interchange specifications, USD supports assembling any number of assets into virtual sets, scenes, shots, and worlds, and allows non-destructive editing with a single, consistent API and stored in a single scenegraph. Although it is common practice to create separate USD files for individual 3D model, USD files can reference other USD files, and even override the contents of referenced USD files, allowing a completely non-destructive workflow. note: Where possible, use USDKit or other system-provided frameworks to work with USD. USDKit is Apple’s system API for working with USD, available in version 27 of Apple operating systems and later. USDKit simplifies integration of OpenUSD into your app with a stable API surface, integrates with other system APIs, and does not require building and bundling USD within your app. USDKit is built on top of OpenUSD, the open-source USD distribution originally developed by Pixar. USD files are interchangeable between USDKit and OpenUSD, so assets created with one can be loaded by the other.

## Topics

### Essentials

- [OpenUSD schemas for AR](usd/usd-schemas-for-ar.md)
- [Schema definitions for third-party DCCs](usd/schema-definitions-for-third-party-dccs.md)
- [Creating USD files for Apple devices](usd/creating-usd-files-for-apple-devices.md)
- [Validating feature support for USD files](usd/validating-usd-files.md)
- [Placing a prim in the real world](usd/placing-a-prim-in-the-real-world.md)
- [Previewing a Model with AR Quick Look](arkit/previewing-a-model-with-ar-quick-look.md)