> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.nvidia.com/holoscan/sdk-user-guide/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/holoscan/sdk-user-guide/_mcp/server.

Holohub is the community collection of reference applications, reusable operators, tutorials, and benchmarks built on top of the Holoscan SDK.
It complements the SDK by showing production-style patterns for real sensor pipelines, AI inference, visualization, and multi-operator graph design.
The [Holohub documentation website](https://nvidia-holoscan.github.io/holohub/) is the best place to browse applications, operators, tutorials, and benchmarks before running locally.

**Holohub is an open, community-driven project and is not an officially supported NVIDIA product.** It is not covered by the NVAIE (NVIDIA AI Enterprise) maintenance plan, so official support channels may not address Holohub-specific issues.

The Holohub repository is hosted on the [NVIDIA GitHub organization](https://github.com/nvidia-holoscan/holohub) and welcomes community participation. If you discover a bug, have a feature request, or want to suggest improvements, please open an issue on the [Holohub issue tracker](https://github.com/nvidia-holoscan/holohub/issues).

Interested in contributing code, documentation, or examples? Read the [Contributing to Holohub guide](https://github.com/nvidia-holoscan/holohub/blob/main/CONTRIBUTING.md) for details on submitting pull requests, code style, and becoming an active contributor to the Holohub ecosystem.

## What Holohub Provides

* **Reference applications** that demonstrate complete end-to-end pipelines.
* **Reusable operators** that can be imported into your own projects.
* **Tutorials and examples** that focus on specific developer workflows.
* **Benchmarks** for evaluating performance and deployment configurations.
* **Command-line interface** for building, running, and managing applications and operators.

## Relationship to the Holoscan SDK

The Holoscan SDK provides the core runtime, scheduling, resources, and built-in operators.
Holohub builds on those SDK capabilities with higher-level, domain-oriented examples and components.

In practice:

* Use the SDK docs to understand core APIs, runtime behavior, and operator development.
* Use Holohub to discover working patterns you can run, inspect, and adapt.

## Operators vs Applications

Holohub separates reusable building blocks from complete solutions:

* **Operator**: a modular processing component (for example, a pre-processing or post-processing stage) designed to be reused across graphs.
* **Application**: a full Holoscan graph composed of operators, conditions, and resources that can be run as a complete pipeline.

This separation helps teams prototype quickly with existing operators, then package complete reference applications for deployment and benchmarking.

## Command-line interface (CLI)

The Holohub CLI provides a unified interface for building, running, and managing applications and operators.

For most users, a single command is enough:

```bash
./holohub run <application_name>
```

This command orchestrates the end-to-end workflow by preparing and launching the required Docker environment, building the selected application, and running it with the application's preconfigured arguments and parameters. For more details, see the [Holohub CLI Guide](https://github.com/nvidia-holoscan/holohub/blob/main/utilities/cli/README.md).

## Repository Layout

The [holohub repository](https://github.com/nvidia-holoscan/holohub) is organized around discoverable components:

* `applications/`: runnable reference applications.
* `operators/`: reusable custom operators.
* `benchmarks/`: performance and scaling evaluations.
* `tutorials/`: focused how-to examples.

Most applications and operators include a `metadata.json` file.
These metadata files describe tags, dependencies, supported platforms, and compatibility details, and are used by Holohub tooling to discover and manage components.

## When to Use Holohub

Holohub is especially useful when you want to:

* Start from a working reference rather than building from scratch.
* Learn best practices for composing operators into robust graphs.
* Compare multiple implementation patterns for similar tasks.
* Evaluate performance with realistic workloads.
* Contribute to the community by sharing your own operators, applications, workflows, and tools.