I have a large collection of poems which I've been meaning to submit for publication, but I need to know which format is used to send these babies. I don't want to send a word document because it seems like I'm just throwing all my work out there without any regard to the risk involved in a plain text document. Which format should I save and send my collection in?
Under no circumstances will you be able to protect textual works. From a technical standpoint. Not on Kindle, not on iBooks, not on Nook, not on your smartphone, not on the web, not in a Word document, not in an encrypted email, not via voice recording. Even if you send a bitmap or some other format, if a human can read it, they can OCR it. Period end of story.
Your protection consists of a) working with reputable publishers b) submitting to reputable sites c) understanding that textual content can be trivially stolen/harvested and d) realizing that if your stuff is good enough to BE stolen, that's actually not a bad problem for a starting author (especially a poet) to have!
Best of luck.