I very much enjoy panel presentations because the content and discussion of each panel is so unique. No two panel discussions are identical, and no two takeaways are identical.

In my books, a plenary talk refers to any session which is a full presentation but is not the main session of an event. Plenary talks can take a wide range of formats, from lecture-based to discussion-based and everything in between.

A keynote speech refers to any talk or presentation which is the main session of a conference or other large event. These cost slightly more due to the increase in participant count and, typically, greater preparation time.

A fireside chat refers to any session which is a main event but is more conversational than a keynote address. Fireside chats typically require less preparation time than keynote addresses and, therefore, cost less.