I was reading Computers, Communications, and Information A User's Introduction (Seventh Edition) by Sarah E. Hutchinson and Stacey C. Sawyer.
The authors consistently used such terms as communications hardware and applications software. I thought we should use communication hardware and application software instead. Why did the authors use nouns of plural form this way?
EDIT: As far as I can remember from English grammar courses, a noun should typically be modified by a single noun preceding it. Rarely have I seen such usages as in the book.