What is the term for messages conveyed through written formats such as letters and emails?

The term that accurately describes messages conveyed through written formats such as letters and emails is "textual messages." This terminology specifically refers to the use of written words to communicate meaning between individuals, which encompasses a wide array of written communication tools. Textual messages can include anything from formal letters to informal emails and other digital text formats. Understanding this distinction is critical, as it highlights the medium of communication—written language—as opposed to other forms such as visual, verbal, or audio messages. Visual messages pertain to images and graphical content, while verbal messages are spoken and rely on oral communication. Audio messages specifically refer to sounds or recordings, emphasizing auditory rather than written communication. Therefore, "textual messages" is the most fitting and precise term in this context.