In the terminal, some commands return long lists of data that exceed the space of the screen. How would one PageUp or PageDown? Or, how would one set the terminal to display a screen's worth of data at a time?

more or less - will dispaly data a screen at a time

To page up or page down use shift + arrow keys - same as most linux terminals

Stu

And you may try out others like QKonsole that can display a scroll bar for easier viewing.