Final answer:
The kind of punctuation that omits the comma after the salutation and complimentary close is typically used in formal letters, where a colon is used after the salutation and no comma follows the complimentary close, such as 'Dear Mr. Smith:' and 'Sincerely'.
Step-by-step explanation:
The kind of punctuation that omits the comma after the salutation and complimentary close in letters or emails is traditionally considered a more formal style. Instead of a comma, a colon (:) is used after the salutation in a formal letter. A common formal salutation is “Dear Mr. Smith:”. For the complimentary close, a common option would be to use “Sincerely” with no comma following it, leaving a space for the signature above the typed name.
It's important to note that in business communications and formal letters, following the proper use of punctuation is essential to convey professionalism. When writing a complimentary close, it's best to include a polite closing line, use a professional complimentary close, and then type your full name. For informal communications, such as those with friends or family, a comma after the greeting and close may be more common.