Express makes it easy to nest routes in your routers. But I always had trouble accessing the request object's .params when you had a long URI with multiple parameters and nested routes.
Let's say you're building routes for a website www.music.com. Music is organized into albums with multiple tracks. Users can click to see a track list. Then they can select a single track and see a sub-page about that specific track.
At our application level, we could first have a Router to handle any requests to our albums.
const express = require('express');