Recently, on the Writers' Cafe forum, a person asked about making a character's text messages in an e-book display differently from the running text.
They wanted the text messages to show up as Courier or something like it. They usually use Microsoft Word to create their manuscripts and Jutoh to make their e-books.
Actually, there is an easy way to do this that few people seem to know about.
In Word, there are at least 5 Styles that you can use to accomplish what you want. However, they only appear in the Style list if you ask Word to show “All Styles.”
• HTML Code
• HTML Keyboard
• HTML Preformatted
• HTML Sample
• HTML Typewriter
You can use one of these for your text messages in your Word file, adjust the indent to what you want, then do a Save as Web Page... to change the Word file to HTML code. On Windows machines, you use the “Filtered” choice of that web page save. On Macs, you use the “Save only display information” choice.
Then, you have to use some sort of conversion engine to make that HTML file into an e-book, either MOBI or EPUB. I use Calibre. (Jutoh may work but I don't use it so I don't know for sure.) I do know that, using Calibre, all of those HTML Styles in Word get converted into your e-book correctly.
I think that HTML Sample is the best because it shows up slightly larger than the others, but all of them end up in your e-book as a monospaced Courier-type font.