What does my section on drumline mean?

For my sophomore year I’ll be joining the drumline. For in general, I got put on bass. But for front ensemble / comp, I’m on something called aux..Okay so I’ve never even touched a drum before until these last few weeks. I’ve been in band for 3 years and I’ve only played wind. Like, Sax and Clarinet…

…I have NO idea what aux is. What’s aux and is that a bad thing?