Final answer:
In a business letter, a colon (:) should follow the salutation, setting a formal tone for the letter and indicating that more information will follow. This punctuation is in line with standard business letter formatting and maintains professionalism.
Step-by-step explanation:
When writing a business letter, it's important to use proper punctuation following the salutation. According to standard business letter formatting, a colon (:) should be used after the salutation. For example, if you were addressing someone directly, the salutation might read 'Dear Dr. Doe:' and then you would leave one blank line after it.
The colon not only introduces the content of the letter but also sets a formal tone for the message to follow. It's distinct from other punctuation marks like the comma or period in that it prepares the reader for further explanation or detail, which in the context of a business letter, is the body text.
Remember, the rest of the letter should be formatted in block style, meaning everything is left-justified, and you should use a professional font like size 12 Times New Roman or Arial. Following these guidelines will help to ensure your business communication is both professional and clear.