Imagine you have a physical Windows installation DVD. That disc contains hundreds of different files—system drivers, installation wizards, setup files, and background images.
The name comes from the "ISO 9660" file system used for optical discs. It is a single file (ending in ) that acts as a container. Because it’s a single file, it is much easier to download and move around than thousands of individual installation folders. What it’s used for what is a windows iso file