what is the difference between ol.Map and ol.PluggableMap in openlayers

Question

I can see 2 kinds of map in openlayers , default map class and ol.PluggableMap .

var map = new ol.Map({
    target: 'm_gmap_1',
    controls: []})

and pluggableMap = new ol.PluggableMap({
 target: 'm_gmap_1',
        controls: []})
}),

could anyone please tell me difference

Answer 1

For an answer, you have to take a look at the PR (Pull Request) "Pluggable renderers" on OpenLayers repository.

You will see that it's to remove some dependencies in particular when you just want to use only one renderer (smaller build)