Operating system 1 - The OS introduced

Loading The OS1 (OCR)

Operating system 2 - Memory management

Loading The OS2 (OCR)

Operating system 3 - Virtual memory

Loading The OS3 (OCR) – Virtual memory

Operating system 4 - Interrupts

Loading The OS3 (OCR) – Interrupts

Operating system 5 - Processor scheduling

Loading The OS4 (OCR) – Processor scheduling

Operating system 6 - Processor scheduling

Loading The OS6 (OCR) – Scheduling algorithms

Operating system 5 - Processor scheduling

Loading The OS7 (OCR) – Backing store and peripheral management