An informational interview is an informal conversation you can have with someone working in an area of interest to you. It is an effective research tool and is best done after preliminary online research. It is not a job interview, and the objective is not to find job openings.
This interview format is more to learn about the company and career you are pursuing from a professional in the field. Don’t ask for a referral or job in the first informational interview. Not all connections will be a referral – and, that’s okay! Be open to the knowledge that some calls will be information gathering and some will lead to referrals.