Dear (Mr., Mrs., Miss, Ms.) followed by last name,
Thank the recipient for taking the time to discuss the position with name of company, and express how you are convinced that your skills and qualifications match the needs of the company.
In the main body of your interview letter, briefly discuss those things that stuck in your mind most about the interview. Mention how much you appreciate the time took to familiarize you with the company, and how you feel you could learn from the position as well.
Reiterate briefly the experience or qualifications you possess, without including information already presented in your resume. Throughout your interview letter, demonstrate your enthusiasm about the possibility of working for the company.
In closing, thank the recipient once more for their time and consideration, and let them know you look forward to hearing from them concerning the job.
Writing an interview letter is actually a simple task, once you understand how to do it properly. Follow the tips and guidelines above, and you will be able to write an interview letter that will make a memorable impression on any prospective employer.