If you're still wondering what is ISO in photography, this helpful guide might help you. But in terms of its meaning, the ...

an ISO utility program is required to identify them and burn the disc with the original file/folder structure. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.

For example, ISO 100 can be stated as 100/21º and ISO 400 as 400/27º. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.