Want more info on your files than the standard icon view provides (after all, it just gives you the file’s name in icon view)? Then turn on Show Item info. This adds an extra line of information below many files and folders that can be very useful. For example, now not only do you get a folder’s name, but just below the name (in unobtrusive light-blue, 9-point type), you’ll see how many items are in that folder.
If the file is an image, the Item Info shows you how big it is. MP3 files show how long the song is, etc. To turn on Item Info for your current Finder window, press Command-J to bring up its View Options. Then turn on the checkbox for Show Item Info. If you want to show the item info for every window (globally), then choose the All Windows button at the top of the dialog.