9 Rungs of the Computer Inferno

Computers are technologically complex but conceptually simple.
(Kudos to Dante and his guide Virgil.)

Nine Rungs of the Computer Inferno

9. Applications Software
8. High-Level Language (HLL) Programs
7. Assembly Language Programs
6. Machine Language (binary) Programs
5. Systems Software (Operating system, etc.)
4. Machine Level (CPU, RAM, etc.)
3. Gate Level (And-, Or-, Not- digital logic gates)
2. Device Level (Transistors)
1. Physics Level (Solid-state)

Levels 1 - 4: Hardware (atoms)
Levels 5 - 9: Software (bits)