CesiumJS Entities

---
name: cesiumjs-entities
description: "CesiumJS entities and data sources - Entity, EntityCollection, DataSource, GeoJsonDataSource, KmlDataSource, CzmlDataSource, Graphics types, Visualizers. Use when adding points, labels, models, polygons, or polylines to the map, loading GeoJSON/KML/CZML/GPX data, or working with the high-level Entity API."
---
# CesiumJS Entities & DataSources

> **Version baseline:** CesiumJS 1.142 -- ES module imports: `import { ... } from "cesium";`
> **Ownership rule:** `*Graphics` classes belong here; `*Geometry` classes belong in cesiumjs-primitives. Properties (SampledProperty, CallbackProperty, MaterialProperty subtypes) belong in cesiumjs-time-properties.

## Architecture

The Entity API is the high-level, data-driven layer of CesiumJS. Entities combine position, orientation, and one or more Graphics types into a single object managed by an EntityCollection. DataSources load external formats (GeoJSON, KML, CZML, GPX) and populate an EntityCollection automatically. Visualizers and GeometryUpdaters translate Entity descriptions into Primitives each frame.

```
DataSource --> EntityCollection --> Entity
                                     |-- position / orientation
                                     |-- billboard / point / label / model / polygon / polyline / ...
                                     |-- properties (PropertyBag)
```

- `viewer.entities` is a shortcut to the default DataSource's EntityCollection
- `viewer.dataSources` holds all loaded DataSources; each owns an `EntityCollection`

## Entity Basics