No, it isn’t.
Server generally has two meanings:
- A piece of software that listens for network requests and then responds to them
- A computer running such a piece of software
A Node.JS server can be either of those.
Generally the server itself is run directly from Node (e.g. with this library) rather than being embedded in another server like Apache (as is most common for PHP).
A browser doesn’t need to be involved at all. If one is, then it will probably be one acting as a client and making a request to the server. That said, tools like PhantomJS can allow a browser to be driven from Node (and other programming languages).
server-side and is therefore not downloaded to the browser. This term
predominantly used on the client-side (also referred to as client-side