Difference between 'run browser' and 'serve'

It seems they have different behavior, I’m trying to implement the cordova-plugin-facebook4 to work with both mobiles and browser.

When i’m launching ‘run browser’, it seems like things are going much further than with ‘serve’, what is the damn difference? I can’t tell what it is, and nothing is told in the docs.

Is it possible to serve the Ionic app, hosted on a server with the ‘run browser’ command?

EDIT : Okay, so browser is a cordova platform, not just a web browser, like a appified web browser, is it? That’s awesome, I now understand what those ‘browser’ plugins are for and how to get them work. Is it usable by a webserver to be served to remote users?

Why doesn’t Ionic serve run this platform this way?

Thanks

Can someone help please?