This is a frequently asked question in General interview questions.   This is such an open-ended question that it can be quite intimidating at times. There are several ways to answer the question, and the interviewer wants to know how much knowledge you have of the industry you have applied for. Research and be prepared, as no one wants to hire such employees who don't know what they are signing for. Also, you must focus on your communication skills, as knowledge alone is not enough. Avoid saying anything you are not sure about, and do not go on for too long. Keep it small, simple, and smart. Here's how you can answer the question - "I learned about the industry when I was first doing my certification course in digital marketing. The best thing that I came across is - this industry is the future of the business. Online marketing, digital marketing, SEO, SEM, SMM, are all a part of the foreseeable future."