Conversation is interactive communication between two or more people. In an academic context, this conversation occurs between individuals with a vested interest in a topic.
If academia were a cocktail-hour, students would be the attendees walking up to people already engaged a conversation and trying to make an entry into the discussion. Those engaged in the conversation are already familiar with the topic and would be experts in the field, faculty, or even students who have some grasp of the subject matter. Just like approaching a real ongoing conversation, one should listen to the conversation for a while to get a feel for the subject matter and to being understanding the topic before jumping in.
"Research 101: Scholarship is a Conversation." Youtube.com, uploaded by Anna Eisen, 12 May. 2014, https://www.youtube.com/watch?v=YGia3gNyHDM
When you engage in course activities, read, listen to lecture, and engage in discussion, believe it or not, you're involved in the conversation. The activities listed above are designed to get you up to speed with the topic of conversation by giving you background information on a topic, tapping your professor's expertise to identify important concepts on the subject, and learning how to use a subject's unique vocabulary that will enable you to discuss the topic with your peers without sounding completely uninformed. For example a physics course may be introducing you to application of various forces that act on a car's wheels as it is driven. It would serve you best to use the appropriate language and talk about friction and the wheels, as opposed to the grippy-slide properties of the turny-bits.
By learning the background on your topic and getting the vocabulary under your belt, you're becoming more authoratative on the topic and are able to ask informed questions and draw your own conclusions about a topic's concepts.