Do publishers only use one word processing program, or can they accept manuscripts from any word processor?
Generally speaking, most traditional publishers do not accept e-mail submissions, so it wouldn’t matter what program you use. You have to print the manuscript out and mail it to them. The format they want it in is generally listed in their submission requirements (ie. double spaced, 12 point Times New Roman font, no italics, no bold, etc). Some small independent publishers accept online submissions and usually ask for the manuscript in an MSWord rich text attachment. But really, you just need to go by the publisher or agent’s guidelines, which can be different from one to the next. Hope that helps.