An informative article on writing dialogue in fiction that includes "visual dialect", to portray regional, national or other differences in speech.

Dialect in fiction can play a powerful part in creating the mood and tone of the story, setting the location, and establishing the relationships between the characters in the story.

Many writers and editors hold with the idea that dialect is an undesirable thing—that it has been done, and overdone, and badly done. Within some stories or books, all those are true . But a little dialect can go a long way toward establishing the mood and locale of the story. Consider it to be like garlic in marinara, or sage in turkey dressing—a little can add to the flavor of the dish, but too much will definitely ruin it. And putting in the wrong spice (garlic in an apple pie, for example) is truly nasty.

First of all, what is dialect? The Compact Oxford English Dictionary defines it as "a form of a language which is peculiar to a specific region or social group." From the viewpoint of dialect speakers, their speech is standard. But from the viewpoint of an outsider, it may appear unlettered, backward, quaint, or even incomprehensible.