Format
The most formal communication format is the one that’s been around the
longest: a standard letter on conventional letterhead. The least formal
business communication is E-mail. Think about this: No matter how serious
your message, no matter how little you know someone, and no matter
to whom you’re writing, if you send your communication via E-mail,
it will be perceived as less formal than if it’s on paper. That doesn’t mean
you should not send important communications via E-mail. It does imply
that critical, sober messages that are sent via E-mail should use a formal
tone and style to compensate for the informal medium.
Here are the least formal media formats:
• flyers
• newsletters