How Should You Send Thank You Letters

Should I Send It Typewritten, Handwritten or via Email?
There are many opinions about the presentation style of a thank you letters. We generally recommend typing the letters in a standard business-style format (much like your cover letters), triple-checking for typos and grammatical errors. You are being evaluated as a professional and typing it confirms that this meeting was important enough to take the time to present yourself in a professional manner.
There are times, however, when it may be appropriate to send a handwritten thank you letter. If someone you know "pulled some strings" to get you the interview or there was a mutual acquaintance of some kind; if you personally know the interviewer; or if the interviewer was an alumni of your institution. Many students choose institution-specific postcards or stationary from the college bookstore. Be sure your handwriting is legible and neat. If you need to expand on some of the issues presented in the interview, then a more lengthy, typewritten letter is better.
Generally speaking, we recommend that you type your thank you letters.
Sending thank you letters via email is fine as long as it fits the "culture" of the organization and is used appropriately. If an employer has an email account on his business card or the school district is very technologically oriented, sending the letter this way may be appropriate. Be sure there is no doubt as to the email address (you may or may not be informed that the message was undeliverable). Format your letter with all the same formalities as a regular thank-you letter. Email tends to make us a bit less formal and you do not want the note to be overly friendly. Try to keep the message to one screen length; employers appreciate brevity. Hard copy will generally be placed in a file, whereas email has a tendency to be read quickly and deleted. You may consider following up the email letter with hard copy.