One thing to really keep in mind is that FAQ in StackExchange-land is two things:

 - That thing with FAQ in the URL
 - The Meta questions tagged [meta-tag:faq]

Of the second point, we do go into this:

https://meta.serverfault.com/questions/1760/server-fault-is-for-system-administrators-in-a-professional-capacity

This is before the big FAQ rewrite, but provides clarification on what the bit after the ellipsis means. 

As for the bolded bit in the question, we went a few rounds on that in the FAQ update process and the thinking behind that verbage boiled down to:

> We have a bunch of people here who ask quite topical questions, and we love them for it; but they don't have 'sysadmin' in their title. People like Network Engineers, Storage Administrators, or Database Technicians. We need something that expresses all of that, but doesn't make the FAQ too long. *Information Technology Professional* seems like the right kind of generic.

Brevity is why we have one title there and not three. 

It is for this reason that the StackExchange FAQ process involves meta-questions tagged with the FAQ tag! Chances are good this very question will get that tag. Because now we can go into a good drill-down of what we mean by that vague title that means different things for different people.

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Going by observed community standards, the ServerFault community defines an *Information Technology Professional* as someone whose day-job is centered primarily around one or more of the following:

 - Servers: Hardware and Operating Systems
 - Networks: Hardware, firmware, configuration, planning and engineering
 - Storage: Hardware, storage area networks, etc
 - Fleet Management IT-style: configuration management, automated deployment, etc
 - Web framework infrastructure: Everything but the code for things like Tomcat, Ruby, php, etc.
 
And even that is an inadequate list and doesn't cover all of the nuance.