http://nkkn5gol4qp6ymwomrjeyiwqrxkthjfqvw7k6jlpafcvslwvbj52caqd.onion/design.html
The basic idea is that there
are many levels, or views, at which a computer can be considered, from the highest level, where the user is running programs, or using the computer, to the lowest level, consisting of transistors and wires. Between the high and low levels are a
number of intermediate levels.