A programming domain defines a specific kind of use for a programming language.
Some examples of programming domains are:
General purpose applications
Rapid software prototyping
Financial time series analysis
Natural language processing
Artificial intelligence reasoning
Expert systems
Gameplay Programming
Relational database querying
Theorem proving
Systems design and implementation
Application scripting
Domain-specific applications
Programming education
Internet
Symbolic mathematics
Numerical mathematics
Statistical applications
Text processing
Matrix algorithms
Image processing/video processing/computer vision