As per Lawkidunya, here below the most famous seven 7 parts of letter are that:
1.Sender’s address. Optimally, you’ll want to have a printed company letterhead.
2.Date. Whoever receives the letter needs to know when the letter was written.
3.Recipient’s address.
4.Salutation.
5.Body.
6.Closing/signature.
7.Enclosures.