# JMap NG Developer Manual

This manual is for developers who want to use JMap NG to create map visualization applications for the web, integrate mapping capabilities into their web applications or extend existing JMap NG tools. JMap NG connects to  your instance of JMap Server and opens JMap projects.

Depending on the needs, one of two different approaches may be selected: using JMap NG Core or using JMap NG App.

Both JMap NG Core and JMap NG App can be easily embedded in you web applications or web sites. This manual explains how to do it and provides running examples that you can use to get started.

## JMap NG Core  <a href="#jmap-ng-core" id="jmap-ng-core"></a>

<figure><img src="/files/UHPCcWu7Vf9R6MfInCLh" alt="" width="375"><figcaption><p>JMap NG Core</p></figcaption></figure>

It’s a library for building map visualization applications for the web. It connects to a JMap Server instance to load and display a map project. It is based on the [MapLibre GL JS](https://maplibre.org/maplibre-gl-js/docs/) open source project. It does not include any UI except for the mouseover popups and basic map controls. It is useful when you need only the map but want to build your own UI around it.

JMap NG Core provides a JavaScript API to perform simple tasks and JMap related tasks like getting a JMap Project, managing layers and accessing feature attributes. It also exposes the full MapLibre GL JS API for other tasks.

The latest version of the JMap NG Core Javascript API documentation is available [here](https://k2geospatial.github.io/jmapserver-ng-core-types/latest/).

## JMap NG App  <a href="#jmap-ng-app" id="jmap-ng-app"></a>

<figure><img src="/files/aC7zwYj3bHUWqTvgsi11" alt="" width="375"><figcaption><p>JMap NG App</p></figcaption></figure>

It’s a complete map visualization application based on JMap NG Core. It provides a complete UI with many ready to use tools such as measuring, selecting, editing features, printing. It does not require any programming but provides a JavaScript API and can be extended by writing JMap NG extensions. JMap NG extensions are modules that plug easily into JMap NG to extend its capabilities, perform custom tasks or to support the integration of JMap NG into another web application.

The latest version JMap NG App Javascript API documentation is available [here](https://k2geospatial.github.io/jmapserver-ng-types/latest/).


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