When I learn for my studies, I usually make summaries using hierarchical layouts in word as follows (example, dots are spaces, or tabs in word);
Europe
......-France
..............oParis
.......-Germany
..............oBerlin
Asia
.......-Japan
.............oTokyo
.......-China
..............oBejing

It would be very helpful if I could easily minimize sub-categories to achieve some overview after which I can 'unfold' categories. This would result in the following:

Europe (+)
Asia (+)

, where the (+) could be pressed for the countries and cities. It is the same as the standard folder structure used in Windows and Mac.
My question is; does anyone know how to do such a thing using Word or some other program?