When you read electronic text, Book Port lets you move through the text by letter, word, sentence (or line), paragraph, and page. It lets you move through digital audio files by three levels of phrase detection which are categorized by sentence, paragraph, and section. If you send a Daisy Digital Talking Book to the unit, you enjoy the additional navigation provided by that file type. This often includes pages and chapters in audio books. Book Port's magazine support makes it easy to move from article to article in magazines you read. This is a great way to browse the excellent magazines available from Web Braille or newsletters that contain specific sections of content. Book Port is powered with two AA batteries that are user replaceable. It runs for well over 60 hours with electronic text on a set of batteries. Digital audio demands a little more from the power supply, but the unit's power consumption is remarkabily conservitive even on the most demanding content.