You can send it as an email attachment, or you can physically hand the letter to them if possible. Here are some resignation letter samples: ...

Q: In our association of 261 units, we have a five-member board. A director resigned by sending an email. The president accepted the resignation but did not put it to a vote by the other board ...

Less than 30 minutes after the Social Security Administration’s chief data officer resigned following a whistleblower ...