Microsoft builds software to help people and companies achieve their full potential. Microsoft's primary goal is to enable customers to be innovative in their own lives, in a variety of ways. Now, the interviewer wants to know how your specialty area of expertise will benefit Microsoft and its valued customers. While your interviewer can tell a lot about your work history from your resume, they are ideally looking to hear about one area of expertise they may not be able to see on your resume that makes you a great fit for the job you are interviewing for. Prior to your interview, try to find that unique match and reiterate it to your interviewer as you answer.