What Does Drive Bay Mean?
A drive bay is an area for adding a drive to a computer. They come in standardized sizes, the most common being 5.25 inches, 3.5 inches, 2.5 inches and 1.8 inches. The sizes refer to the actual size of the discs rather than the drives. Most of the devices for these bays are disk drives, but other peripherals can occasionally be used.
Techopedia Explains Drive Bay
Drive bays allow certain peripherals, mostly disk drives, to be plugged into a computer. While disk drives are the most common, it is possible to use other peripherals, including card readers, USB ports, fan controllers and even small LCD monitors.
