Nepal Police2080 BSQuestion 2 of 14
What is an Operating System? Describe basic memory management strategies in Operating System.
5 marks
Question source
- Exam year
- 2080 BS / 2024 AD
- Level
- Sub-Inspector (Prabidhik – IT/Computer)
- Paper
- Paper II – Professional and Service Specific Test
- Section
- Section A
Model answer
An Operating System (OS) manages hardware/software resources and gives user interface. Examples: Windows, Linux.
Basic memory management strategies:
- Contiguous allocation — Each process gets one continuous block. Simple but causes fragmentation (free holes).
- Paging — Divides RAM into fixed pages and process into same-size pages; pages can sit anywhere. Removes external fragmentation; used with virtual memory.
- Segmentation — Divides by logical parts (code, data, stack) of variable size; easier protection/sharing but complex.
- Virtual memory (paging to disk) — Uses SSD/HDD as extension of RAM. Inactive pages swapped out, active pages kept in RAM, so large programs run on small RAM.
- Protection and sharing — Each process isolated; shared libraries allowed read-only to save RAM.
In short: OS fits many programs safely into limited RAM using paging + virtual memory.