Internet relay chat or irc is a protocol for handling discussions. It is often used to talk about development of software projects and ask for help in using them, and problem-solving. Some non-technical users may be initially intimidated by irc, and it is true that some prominent individuals on some chatrooms have rather strict interpretations of and expectations of etiquette, but typically a short guide will be enough to get by and it may be considered that the conventions of irc are rather less stringent and complex than might be the case on Twitter or Mastodon. You will be expected to have done some work before showing up to ask questions. Find out as much as you can about your problem so that you will be ready to give information.
A server is a computer that serves files like waiting staff serve dishes in a restaurant. (Waiting staff usually take food from the pass and drinks from the bar and bring them to customers who have asked for them, but they might also deliver messages and even items to the kitchen, receive deliveries and the like. In the same way, the term 'server' is becoming something of a misnomer as the computers which are serving files users request are also increasingly receiving them.) A virtual server is a computer that exists in the "imagination" of another computer. Much as you might open a calculator on your mobile phone and see a virtualisation ie. a mock-up of the kind of physical calculators that were common in the 1980s, a virtual server does not exist in physical form. Instead, the calculations that would be made by such a computer are made inside of another computer. What this means is practice is that virtualised "computers" that exist in the memory and the processors of physical computers may be rented inexpensively to run as servers for any number of purposes on the web. Marginálie currently exists as two virtual servers. One handles the website and the wiki. Another handles the social media instance which runs Pleroma. Should you wish to imagine what this looks like, there are physical racks of servers somewhere in Germany (computers which are optimised to take up little room and to stack on top of one another rather than to sit with a monitor on a desktop so that they look like the server cupboard you might see at work). Each of these computers is then pretending to be countless other computers each of which will be doing something like the make believe computers running Marginálie. If you are struggling to understand the advantage or thinking this is all rather inefficient or inconvenient, you are not far wrong. Virtual servers are great for small projects, hobbyists, and prototyping. Ideally, Marginálie would like to move to self hosting with its own rack computers. That, however, is prohibitively expensive.