Business letter

A business letter is a letter written in formal language, usually used when writing from one business organization to another, or for correspondence between such organizations and their customers, clients and other external parties. The overall style of letter will depend on the relationship between the parties concerned.
Parts of a business letter.
Business letters (in the United States) usually contain the following information (in this order):
Date of writing.
Return address
Recipient's address
Salutation or Greeting
Message (body of the letter)
Closing
Signature, printed name, and position of sender
In some situations, a business letter may also include the following optional information:
Enclosures (Encl:)
Carbon Copy Recipients (cc:)
Reference Initials (of the typist)

Example of a block-style business letter
January 17, 2009Name of SenderAddressName of ReceiverAddressMarawi City, Lanao del SurDear Mr. Hayat Shay:This letter is typed flush with the left margin. Note that all lines begin at the left margin including the date, complimentary close, and signature block. They start from the center, or slightly to the right off center on the page. Some authors refer to this form as the “modified block with block paragraphs.”This style is usually typed with mixed or standard punctuation. The salutation is followed by a colon, and the complimentary close, by a comma. This form of punctuation is widely used in most business correspondence.To facilitate typing the date and the closing lines, set the tabular stop at the center or slightly off to the right of the paper so that you can tabulate it whenever you wish.Remember to always leave a space between the valediction and the name, so the person who is sending this has plenty of room to sign the letter.
Sincerely,
*Signature*