I've hooked up with some networks who mail "text only" internally. But I'm curious as to what everyone's definition of text only really is. I'll receive "tex-only" creatives from a network in rich text format which is clearly formatted with font styles. To me, text only means plain text. AKA my header reads Content-Type: text/plain; I'm wondering if some people call it "text only" just because there are no images. When you mail "text only" is it text/plain or text/html, multipart/alternative (w/o images)?