This question seems simple, so many people fail to prepare for it, but it's crucial. Here's the deal: Don't give your complete employment (or personal) history. Instead give a pitch—one that’s concise and compelling and that shows exactly why you’re the right fit for the job. Start off with the 2-3 specific accomplishments or experiences that you most want the interviewer to know about, then wrap up talking about how that prior experience has positioned you for this specific role.
Tip: Employers often ask this question to identify why you might be more qualified than other candidates they’re interviewing. To answer, focus on why hiring you would benefit the employer. Since you don’t know the other applicants, it can be challenging to think about your answer in relation to them. Addressing why your background makes you a good fit will let employers know why your traits and qualifications make you well prepared.
Any candidate can read and regurgitate the company’s “About” page. So, when interviewers ask this, they aren't necessarily trying to gauge whether you understand the mission—they want to know whether you care about it. Start with one line that shows you understand the company's goals, using a couple key words and phrases from the website, but then go on to make it personal. Say, “I’m personally drawn to this mission because…” or “I really believe in this approach because…” and share a personal example or two.