If those three acronyms made sense to you, congratulations, you're a designer! Or at least someone who's in the loop. While Dropbox has a commanding presence on mobile and on the desktop, there are some moments when all you have is a web browser. And usually in those moments, download a large Photoshop PSD file is not only time consuming, it might also be futile since you wouldn't have the proper software to open it. Thank goodness, then, that Dropbox thought of supporting those files out of the, well, box.