Prof comm is short for professional communication, a class that builds the writing, speaking, and people skills you need at work.
You might draft a business email to a client, or give a short presentation and get feedback on how clearly you came across.
A nearby word worth separating: this kind of class is not about casual chat. The focus is workplace situations, where tone and clarity matter more than they do in everyday conversation.
In one common unit, you might write a short cover email to a hiring manager and revise it until the tone sounds polite and direct. The email itself is the skill being practiced.
In another, you might explain a project update to three classmates playing the role of managers, then hear what worked and what was unclear. This is where the interpersonal side shows up: speaking, listening, and adjusting on the spot.
A professional communication class deals with workplace writing and speaking rather than everyday conversation or literature-style essays. The focus is practical: emails, reports, presentations, and conversations with colleagues, not casual texting or literary analysis.