They want to know what makes you the best person for the job and want to know what you might be able to bring to the table that others can't. In preparing for this question, I'd suggest first making a list of skills and strengths you have. They can range from more generic to more unique. A good answer to this question isn't just about listing a unique skill you have. Being able to hold your breath for 2 minutes under water may very well set you apart from other candidates, but if it's not relevant to the job, it's not a good one to share.Remember that this question is about what's going to really set you apart. It's a time to be confident in your abilities and really sell yourself.