Older professor, bespectacled, grey hair, formal wear, standing in front of a green chalkboard, filled with assembly code, diagrams of CPU architecture, registers, ALU, buses, microarchitecture, x86 instruction set, 80x86 processor, computer system organization, lecturing, explaining complex concepts, university classroom setting, natural light streaming through the window, wooden desks and chairs, students taking notes in the background, soft focus, shallow depth of field, warm lighting.