There are many options when it comes to stock and inventory control systems. Some are for the masses, and other organizations may have proprietary software. When asked about your exposure to these programs, it is important to remember that most of them function the same because the desired outcome is always similar. If you know one, you should be able to understand another more easily. Avoid focusing on what you don't know and focus on what you DO know. Assure the interviewer that you can learn their system quickly.