My Photo Stream
When you set up your device to use Photos with iCloud, you can turn on the My Photo Stream feature (not available for new accounts).
With My Photo Stream, photos taken in the last 30 days (up to 1000) are uploaded to iCloud and accessible on any device where you’re signed in with the same Apple ID and the iCloud Photos feature is turned on. My Photo Stream doesn’t upload videos or Live Photos. See the Apple Support article My Photo Stream.
Photos stored in My Photo Stream don’t count toward your iCloud storage.
If you turn on both iCloud Photos and My Photo Stream on an iPhone, iPad, or iPod touch, photos that you take with that device are uploaded to both iCloud Photos and My Photo Stream. For more information about iCloud Photos and how it differs from My Photo Stream, see the Apple Support article About iCloud Photos and My Photo Stream.
Note: To prevent unintended or excessive use, My Photo Stream limits the number of photos that can be uploaded within a given hour, day, or month. See the Apple Support article My Photo Stream and Shared Albums limits.