# Map Layers

In JMap, map data is organized in layers. These layers are displayed transparently on the map and are piled one on top of the other. They are independent from one another and can be turned on or off. Layer order is important as some more opaque layers can hide elements found in lower layers. A layer must be visible in order to be displayed on a map and it must be selectable in order for users to select its elements.

The JMap administrator creates project layers as they appear when the project is opened. You can change the order of the layers as well as other settings; these changes will be lost when closing the application unless saved in a context. Refer to [Layer Settings](/en2/applications-user/jmap-pro-user-guide/map-layers/layer-settings.md) and [Map Contexts](/en2/applications-user/jmap-pro-user-guide/tools/collaboration-tools/map-contexts.md) for more information.

The JMap administrator also determines the frequency of automatic updating for each layer, i.e. how often your application will automatically reload the layer data from the JMap server.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.k2geospatial.com/en2/applications-user/jmap-pro-user-guide/map-layers.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.