---
title: "ClassId"
---
<!-- DO NOT EDIT! This file was auto-generated by crates/build/re_types_builder/src/codegen/docs/website.rs -->

A 16-bit ID representing a type of semantic class.


## Arrow datatype
```
UInt16
```

## API reference links
 * 🌊 [C++ API docs for `ClassId`](https://ref.rerun.io/docs/cpp/stable/structrerun_1_1datatypes_1_1ClassId.html)
 * 🐍 [Python API docs for `ClassId`](https://ref.rerun.io/docs/python/stable/common/datatypes#rerun.datatypes.ClassId)
 * 🦀 [Rust API docs for `ClassId`](https://docs.rs/rerun/latest/rerun/datatypes/struct.ClassId.html)


## Used by

* [`ClassDescriptionMapElem`](../datatypes/class_description_map_elem.md)
* [`ClassId`](../components/class_id.md)
