Can someone explain the difference between WP_Site_Query and WP_Network_Query in WordPress 4.6?

• WP_Network_Query() : Core class used for querying networks.
• WP_Site_Query() : Core class used for querying sites.
• WP_Term_Query() : Class used for querying terms.

Are there examples when you would query the Network vs. the Site vs. Posts?

Wouldn’t a WP_Site_Query just be a WP_Query? I’ve been hoping for a way to query posts across multiple sites but I don’t think this is that.

I wonder if Multisite Focused Changes in 4.6 would help…