LETTER (5 letters) A written note is a form of communication that can be used to convey information. A MEMO is a type of written note that is typically used in a business or professional setting. It is usually brief and concise, and is often used to communicate instructions or updates. A LETTER is another type of written note that is typically more formal than a MEMO. It is often used to communicate with people outside of the organization, such as customers or vendors.