occassionally my screen goes to a series of historical windows (previous apps, searches, etc) how does that come up? Ready to select an app
the screen changes to show a series of windows (chronological in order) of the last usages of the phone
How do I access that?  Where is the command or what is the finger-to-screen command?
This "Menu" comes up when you either long-press the Home button or the Multitask button,
which is usually located to the right of the Home key.

If you are using a Samsung device, this button is usually located to the left of the Home key.