What's the difference between children's photography CD burning and U disk copying?

CDs can generally be played automatically on computers, especially DVDs at home. Of course, the whole CD can also be copied into ISO format, or played directly on the computer with virtual cd software. Using a USB flash drive directly usually means copying files and playing them on a computer, but if it is made with high-end software, there will be many files, such as the separation of the beginning and the end ... In short, there will be many independent video files.