A poster is a visual representation of research. A poster session or poster presentation is simply a presentation that uses a poster you create as a visual aide and way to display your ideas.
Your poster is a tool for conveying information. It’s a means to an end. While designing it, you should strive to make it look good, but never forget the information is the most important thing!
One of the most important parts of a poster session is that, after the initial session, the poster can still be valuable as a display or tool. Your poster may help a student understand your topic in the coming semesters!