The 'Operating system' dimension shows the operating system and version that the visitor used. If you have features on your web-property that are OS-specific, this dimension helps you understand which operating systems are most common.
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This dimension references a lookup table internal to Adobe. The lookup value is based on the User-Agent HTTP header in image requests. If you use an AppMeasurement library (such as through Adobe Experience Platform Launch), this dimension works out of the box.
Dimension values include operating systems that visitors use. Examples include "Windows 10" , "OS X 10.15" , and "Android 9" .