Summary
This template superimposes a location marker and a label on an image. It was created so that skill perk information can be displayed on top of a perk tree image, in conjunction with the Perk Tree template. However, it could be used in conjunction with any other "container" template that generates the image. In fact, it could even be used without any image at all, to place markers/labels at arbitrary locations on a page.
The template is derived from Location map on Wikipedia. Although the basics of the template functions are still the same as the Wikipedia template, it's essentially been irreversibly changed. UESP-specific functions have been added; new parameters and features have been added; label positioning bugs have been fixed.
Parameters
The parameters listed under "Inherited Parameters" are ones whose values can be initialized using {{#inherit}}. In most cases these are parameters that should be applied uniformly to all of the Image Marks shown on a given image. The easiest way to set these parameters using the Perk Tree Setup template.
Examples
See Perk Tree.