What is Page shelf?

The Pages shelf splits a view into a sequence of pages, one per member of the field you place on it, showing a single page at a time along a common axis.

It comes with a control offering forward, back, and an automatic play through the sequence at a chosen speed, with an option to show a trail of previous positions.

The usual use is animating change over time: put a date part on Pages and watch a scatter plot move, which makes a trend obvious in a way a static chart does not.

Its limitation is that it does not survive publishing — the page control is not available to viewers on Server, so it is a presentation and analysis tool rather than a dashboard component.