> What is a domain? A set of disciplines, or majors, other than computer-science (or alternatively something other than core programming/software-engineering s

> What is a domain? A set of disciplines, or majors, other than computer-science (or alternatively something other than core programming/software-engineering skills). The word is typically used in CS/sofware-engineering circles. An (arguably crude) example: Think of who designed an mp3 encoder/decoder? A programmer? Does becoming a good programmer and/or getting a typical 4 year CS degree, sufficient to come up with an audio encoder/decoder? No. You have to understand audio signals, their properties, learn how to analyze them, etc. That requires knowledge from the disciplines of physics, and electrical engineering (e.g., digital signal processing), maybe even some biology of sound. And if you learn that, you become a part-programmer, part-acoustic-engineer. That "acoustic-engineer" bit is your "domain expertise", i.e., something you need to know beyond CS to get your work done. You might say, "why do I have be an acoustic engineer? why can't I, as a programmer, work with another guy, who is not a programmer but an expert acoustic engineer?". Yes you can. In that case, you're being the software guy, and he's being the domain-expert. Sometimes collaboration between a software-engineer and a domain-expert works. Sometimes it helps if the software-engineer himself develops domain-expertise (so one guy playing two roles). Domain expertise is not limited to one domain only. It could be no-domain (a pure CS programming, like database, web-development etc, although you could call them domains within CS), or a domain consisting of multiple disciplines (audio-processing comprising physics, DSP), or multiple domains (acoustic-engineering plus submarine-engineering, for example), and so on. More: https://www.google.com/search?q=what+is+a+domain+expert https://www.google.com/search?q=what+is+a+domain+expert