# FAQs

<details>

<summary>How is OS NGD API – Features different from OS Features API?</summary>

The [OS Features API](/os-apis/accessing-os-apis/os-features-api.md) is based on the OGC standard Web Feature Service (WFS) and provides access to OS OpenData and OS Premium Product data. It does not give access to any OS NGD data.

OS NGD API – Features gives you simple access to the OS NGD using the latest in API standards (based on the [OGC API – Features specification](https://ogcapi.ogc.org/features/)). As the new API uses the latest standards, it's easier than ever before to quickly discover what OS NGD data is available and create your own bespoke data selections with more understandable filtering options. Ultimately, this will help accelerate your time-to-value by making it easier to build awesome things with our trusted geospatial data.

Please see the [What data is available? page](/os-apis/accessing-os-apis/os-ngd-api-features/what-data-is-available.md) for the full list of OS NGD feature types included in the OS NGD API – Features.

</details>

<details>

<summary>Why does OS NGD API – Tiles only include a subset of OS NGD feature types and their attributes?</summary>

A key benefit of vector tiles is that they comprise layers of vector features optimised for caching and scaling that can render quickly. As a result, to ensure the vector tiles are lightweight and offer a smooth user experience, we only use the OS NGD feature types required to create a complete contextual basemap.&#x20;

The OS NGD API – Tiles basemap does not contain every OS NGD feature type, nor the complete list of attribution available within the feature types that are included; we have purposefully only selected feature types and a subset of attribution from them that are useful for visualisation as this keeps the tiles lightweight and quick to render. Even with minimal attribution, map developers can apply styles and interactivity to vector features that is just not possible with raster maps.&#x20;

The inclusion of unique identifiers (where available) allows you to cross-reference with the full product (for example, with [OS NGD API – Features](/os-apis/accessing-os-apis/os-ngd-api-tiles.md)).

Please see the ['What data is available?' page](/os-apis/accessing-os-apis/os-ngd-api-tiles/what-data-is-available.md) for the full list of OS NGD feature types included in the OS NGD API – Tiles basemap. Additional data overlays of OS NGD datasets are available to add additional information to the basemap, depending on your needs.&#x20;

</details>

<details>

<summary>When is OS NGD API – Tiles updated?</summary>

The OS NGD API – Tiles basemap is updated weekly. This means that the OS NGD data is updated with the latest available data every week, usually by Monday. The data used to update the API is taken from the previous Wednesday, ensuring that we’ve updated the vector tile cache with the latest OS OpenZoomstack and OS NGD data available at the time.

</details>

<details>

<summary>When is OS NGD API – Tiles updated?</summary>

The OS NGD API – Tiles basemap is updated weekly. This means that the OS NGD data is updated with the latest available data every week, usually by Monday. The data used to update the API is taken from the previous Wednesday, ensuring that we’ve updated the vector tile cache with the latest OS OpenZoomstack and OS NGD data available at the time.

</details>

{% hint style="info" %}
Additional general FAQs and answers about OS APIs are available on the ['OS Data Hub FAQs: Plans' page](https://osdatahub.os.uk/support/plans) and ['OS Data Hub FAQs: Account and API' page](https://osdatahub.os.uk/support/faqs/account-and-apis), for example, 'What's a project?', 'How do I generate an API Key?', 'What throttling is applied to the APIs?'.
{% endhint %}


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