"Thank You" For The Interview
Sending a "Thank You" is a great way to stand out after an interview and can position you as the ideal candidate for the job long after you have left the interview. I highly suggest this be done after every interview (unless you absolutely are not interested in the position).
Use E-mail - Snail mail represents the ultimate formality and personalization when it comes to important matters, but due to the increased pace of the interview and hiring process, email has now become the accepted standard.
Be Timely - Timing is everything in the interview game; there's no better way to let the hiring manager know of your appreciation for the interview and your interest in the position than a thoughtul follow up. Send your "thank you" within 24 hours of the interview.
Keep it Short & Sweet - In a world where a resume only gets 6 seconds of the hiring manager's time, you can be certain your "thank you" note will receive a similar scan. Avoid being verbose at the expense of turning off the hiring manager in what will be your final impression before the job offer stage.
Thank Everyone - Time is valuable for every interviewer who spends time with you. Assume that all interviewers will be weighing in on whether or not to hire you. Whatever you do, DO NOT copy/paste the same note to each person. Colleagues talk and there's nothing worse than being the topic of the copy/paste thank you conversation.
If you follow these simple steps, you'll know that you have done everything possible to make the most professional impression and ensure you are remembered. Good Luck!