Purpose of a virtual path prefix in Express - express

Question

The way to serve static on the server side seems pretty straightforward in Express:
To serve static files such as images, CSS files, and JavaScript files,
use the express.static built-in middleware function in Express.
Pass the name of the directory that contains the static assets to the
express.static middleware function to start serving the files
directly. For example, use the following code to serve images, CSS
files, and JavaScript files in a directory named public:
app.use(express.static('public'))
Now, you can load the files that are in the public directory:
http://localhost:3000/images/kitten.jpg
http://localhost:3000/css/style.css
http://localhost:3000/js/app.js
http://localhost:3000/images/bg.png
http://localhost:3000/hello.html
Express looks up the files relative to the static directory, so the
name of the static directory is not part of the URL.
To use multiple static assets directories, call the express.static
middleware function multiple times:
app.use(express.static('public'))
app.use(express.static('files'))
Express looks up the files in the order in which you set the static directories with the express.static middleware function.
I get the idea of a virtual path prefix, but why would you use it?
To create a virtual path prefix (where the path does not actually
exist in the file system) for files that are served by the
express.static function, specify a mount path for the static
directory, as shown below:
app.use('/static', express.static('public'))
Now, you can load the files that are in the public directory from the /static path prefix.
http://localhost:3000/static/images/kitten.jpg
http://localhost:3000/static/css/style.css
http://localhost:3000/static/js/app.js
http://localhost:3000/static/images/bg.png
http://localhost:3000/static/hello.html

Answer 1

I know it's a little late, but hope this could help you. BTW, I take no credit for the answer, just went to dive a little deeper on your concern and found this.
This technique comes in handy when providing multiple directories to serve static files. The prefixes are used to help distinguish between the multiple directories.
If you would like to dig deeper. I found it on this link:
https://guide.freecodecamp.org/nodejs/express/