Select this option to add bookmarking capabilities to any of your iTunes tracks.

I’ve noticed that when I download an audiobook from the iTunes Store, that file is bookmarkable. How can I make one of my own MP3 files bookmarkable, such as a recorded lecture from my college class?

iTunes automatically “bookmarks” audiobooks, TV shows, movies, and podcasts that you download from the iTunes Store—meaning, iTunes will remember your position in those files, so you can pause them in the middle, play something else from your library, and when you come back to play the bookmarked file again, it picks up right where you left off. This incredibly convenient feature prevents you from having to fast-forward or rewind through extremely lengthy files, and when you transfer these files to your iPod, your last-remembered position will sync there as well.

But if you’re adding your own content to iTunes from outside the iTunes Store, you have to work a bit of your own bookmarking magic. To add this bookmarking feature to any file in your collection, simply select the track in iTunes, choose File > Get Info, and click the Options tab. Check the box that says Remember Playback Position, and you’re all set!

While you’re there, the Media Kind pop-up menu lets you choose whether you consider your track to be a Music file or an Audiobook file, which determines which section of your library will house that track. And the Skip When Shuffling option will prevent that boring lecture from interrupting your music when you’re listening to iTunes in shuffle mode.