Notification Grouping
Explanation
Ten edits of the same page would be ten lines in your notifications menu. Instead, events that resemble each other are delivered as a single notification, which carries a count and a "Details" section listing each event it stands for.
Two events are grouped when they are of the same type and concern the same page. Events of different types are grouped as well when they were triggered during the same editing session. Events that concern no page at all are grouped by type alone.
The same groups are used on every channel, so an email covering a day of activity carries the same single entry rather than ten.
Wiki administrators can replace this behaviour with another grouping strategy, and choose separately how grouped events are spread over emails. Both are described on the Notifications Grouping Strategies page.
FAQ
Why does a group of mine hold events from different pages?
Because your wiki uses a grouping strategy other than the default one, which groups by event type only.
