@Robrgrm-
Many movies are filmed in formats even wider than a standard wide screen TV screen. When shown on a standard TV screen in their full width, they don't fill the screen vertically, leaving black bars at top and bottom.
This is just the opposite of viewing old movies and TV shows that were made to be viewed on old narrower screens. They can be shown in full height, but leave black bars on both sides.
If the top and bottom bars really bother you, your TV may have controls that will allow you to enlarge the picture size to eleminate the bars, but then the right and left ends of the picture will be off the screen. There may even be an option to fill the screen by sqeezing the image horizontally, distorting everything to make it appear taller and skinnier. Look for controls labeled Zoom, Size, Picture, Ratio, or something similar.
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