Which is the role of Apache2 HTTP server if it concerns Ubuntu 18.04 Desktop in its original form, means as released by Canonical?
I wonder if Apache2 installed and running on 18.04 machine here is result of distro makers' decision or rather result of past package installation on my own. Currently HTTP server is not needed so if stock 18.04 does not need that, it is likely to be removed from machines here.
Any idea?
There are plenty of blogs and sources of other kinds explaining Apache2 installation. I didn't manage to find there answer to question asked here. No wonder Apache2 installation and Apache2 role in Bionic Beaver are two different problems.
It's a web server. It's not needed by Ubuntu in the standard desktop installation, and is neither part of the standard desktop or server installation.
It's almost certainly installed as a result of some action by you, and can be removed if you don't see a need for it.