# Layer Concept <a id="layer-concept"></a>


__🔙[Back to Homepage](../intro.md)__

Geoinformation systems (GIS) visualize data by stacking layers on top of one another to create maps. Every layer represents one set of information.
This is a vital concept to understand since analysis, as well as visualisation of data, is based on it.

:::{figure} ../../../fig/Layer_concept.png
---
name: layer_concept_wiki
width: 500 px
---
The layer concept in GIS applications. Source unknown. All rights reserved. This content is excluded from our Creative Commons license.
:::


## Hide and show layers <a id="hide-and-show-layers"></a>

- Check the check-box in the Layers panel on the bottom left:

<video width="100%" controls muted src="https://github.com/GIScience/gis-training-resource-center/raw/main/fig/qgis_show_hide_layer.mp4"></video>

## Have you "lost" your layer? <a id="have-you-lost-your-layer"></a>

Right click on your layer → `Zoom to layer(s)`.

<video width="100%" controls muted src="https://github.com/GIScience/gis-training-resource-center/raw/main/fig/qgis_zoom_to_layer.mp4"></video>

## Move layers in the hierarchy <a id="move-layers-in-the-hierarchy"></a>

* Move a layer up and down in the Layer panel by drag-and-drop.
* Move a layer to the top: Right click on your layer → `Move To Top`.

<video width="100%" controls muted src="https://github.com/GIScience/gis-training-resource-center/raw/main/fig/qgis_layer_hierarchy.mp4"></video>

## Change Layer Name <a id="change-layer-name"></a>

Right click on your layer → `Rename Layer`.

<video width="100%" controls muted src="https://github.com/GIScience/gis-training-resource-center/raw/main/fig/qgis_rename_layer.mp4"></video>

## Layer properties <a id="layer-properties"></a>

Each layer has additional properties that you can view and customise. The most important are: 

* __Information:__ An overview of the layer name, file format, storage location, spatial extent, number of features (objects),...
* __Symbology:__ Display mode of the layer, style, transparency,...

<video width="100%" controls muted src="https://github.com/GIScience/gis-training-resource-center/raw/main/fig/qgis_layer_properties.mp4"></video>