The Network macro allows you display the people a particular user is following, or people who are following that user. Following someone is a useful way to get notifications about their activity, and this network information is also available on each user's profile page.
We ended support for the Network macro in Confluence 7.0, and hid it from the macro browser. Any existing instances of this macro will still work, but you won't be able to insert this macro into the editor using the macro browser.
End of support means Atlassian will not fix bugs related to this macro in Confluence 7.0 or later versions.
To check whether a macro is used in your site, go to General Configuration > Macro Usage.