The term programming domain is mostly used when referring to domain-specific programming languages.
It refers to a set of programming languages or programming environments that were written specifically for a particular domain, where domain means a broad subject for end users such as accounting or finance, or a category of program usage such as artificial intelligence or email.
Languages and systems within a single programming domain would have functions common to the domain and may omit functions that are irrelevant to a domain.
[1] Some examples of programming domains are: Other programming domains would include: This programming-language-related article is a stub.
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