Yes, understanding all the Nodes, especially with complex Node Trees takes time and practice. Don’t worry, you’ll get there 🙂
The Map Range Node simply takes a value and changes ( ‘maps’) that to another. But the input, coming from another Node is usually not one single value and so the Map Range then changes each of those values.
Keep going, understanding Nodes (and many other aspects of Blender and 3D in general) will come with time.
