Operating System (OS) is one of the most important topics in Computer Science for examinations such as Bihar STET, BPSC, SSC, Banking, Railway, CTET and other competitive exams.
Questions are commonly asked from process management, CPU scheduling, memory management, deadlocks, file systems, I/O management, synchronization, virtual memory and operating system types.
1. What is an Operating System?
An Operating System (OS) is system software that acts as an interface between the user and computer hardware.
It manages:
CPU
Memory
Files
Input/Output devices
Processes
Security
Resources
Simple Definition
An Operating System is system software that manages computer hardware and provides services to application programs.
Examples
Windows
Linux
macOS
Android
UNIX
Ubuntu
iOS
2. Main Functions of Operating System
The major functions of an OS are:
Process Management
Memory Management
File Management
Device Management
I/O Management
Security and Protection
Resource Management
User Interface
Error Detection
Networking
Accounting and Monitoring
3. Operating System as Resource Manager
An operating system manages various resources.
| Resource | Managed By OS |
|---|---|
| CPU | Process Management |
| RAM | Memory Management |
| Files | File Management |
| Keyboard/Mouse | Device Management |
| Printer | I/O Management |
| Storage | File System |
Therefore, OS is often called a Resource Manager.
4. Types of Operating Systems
Important types include:
Batch Operating System
Multiprogramming OS
Multitasking OS
Multiprocessing OS
Multithreading OS
Time-Sharing OS
Real-Time OS
Distributed OS
Network OS
Embedded OS
Mobile OS
5. Batch Operating System
In a batch operating system, jobs are collected and executed in batches without direct interaction between the user and computer during execution.
Features
Jobs are grouped together.
Little or no user interaction.
Suitable for repetitive jobs.
High turnaround time can occur.
Example
Payroll processing is a typical batch-processing application.
6. Multiprogramming Operating System
In multiprogramming, multiple programs are kept in memory simultaneously.
When one process waits for I/O, the CPU can execute another process.
Main Objective
Increase CPU utilization.
7. Multitasking Operating System
Multitasking allows multiple tasks to appear to run simultaneously.
Example:
A user can:
Browse the internet
Play music
Edit a document
at the same time.
8. Multiprocessing Operating System
A multiprocessing OS uses two or more processors/cores to execute processes.
Advantages
Higher performance
Increased reliability
Parallel execution
Better CPU utilization
9. Multithreading
Multithreading allows multiple threads to execute within a process.
Thread
A thread is the smallest unit of CPU execution within a process.
Example:
A web browser may use different threads for:
Page rendering
Network communication
User interface
Background tasks
10. Time-Sharing Operating System
A time-sharing OS allows multiple users or processes to share CPU time.
CPU time is divided into small units called time slices or time quantum.
Important
Round Robin scheduling is commonly associated with time-sharing systems.
11. Real-Time Operating System
A Real-Time Operating System (RTOS) must respond to events within specified timing constraints.
Types
Hard Real-Time
Missing a deadline may cause serious system failure.
Examples:
Aircraft control
Critical industrial control systems
Soft Real-Time
Missing a deadline is undesirable but may not cause catastrophic failure.
12. Distributed Operating System
A distributed OS manages a group of interconnected computers and attempts to make them work together as a coordinated system.
Advantages
Resource sharing
Load balancing
Reliability
Distributed processing
13. Network Operating System
A Network Operating System provides services to computers connected through a network.
Examples include systems used for:
File sharing
Printer sharing
User management
Network security
14. Kernel
The kernel is the core component of an operating system.
It directly interacts with hardware and manages critical system resources.
Main responsibilities
CPU management
Memory management
Device management
Process management
System calls
15. Shell
A shell provides an interface through which users can interact with the operating system.
Examples:
Command Prompt
Bash
PowerShell
Kernel vs Shell
| Kernel | Shell |
|---|---|
| Core of OS | Interface to OS |
| Manages hardware/resources | Accepts user commands |
| Runs with high privileges | Provides user interaction |
16. System Calls
A system call is a mechanism through which a user program requests a service from the operating system kernel.
Examples:
Process creation
File opening
File reading
File writing
Memory allocation
Common categories:
Process control
File management
Device management
Information maintenance
Communication
Protection
17. Process
A process is a program in execution.
For example:
A program stored on disk is passive.
When it starts executing, it becomes a process.
Process contains
Program code
Data
Stack
Heap
Program Counter
CPU registers
18. Process States
A process commonly passes through these states:
New
Ready
Running
Waiting/Blocked
Terminated
State Flow
New
↓
Ready
↓
Running
↓
Waiting
↓
Ready
↓
Running
↓
Terminated
19. Process Control Block (PCB)
The Process Control Block stores important information about a process.
It may contain:
Process ID
Process state
Program Counter
CPU registers
CPU scheduling information
Memory-management information
Accounting information
I/O status information
Exam Point
PCB is maintained by the Operating System.
20. Process vs Program
| Program | Process |
|---|---|
| Passive | Active |
| Stored instructions | Program in execution |
| Does not have execution state | Has execution state |
| Static | Dynamic |
21. Thread
A thread is the smallest unit of execution within a process.
Threads of the same process generally share:
Code
Data
Heap
Open resources
But each thread generally has its own:
Program Counter
Registers
Stack
22. Context Switching
When CPU changes from one process/thread to another, the OS saves the state of the current process and loads the state of another.
This is called context switching.
Important
Context switching creates overhead because CPU time is spent saving and restoring state rather than directly executing user work.
23. CPU Scheduling
CPU scheduling determines which ready process gets the CPU.
Main Objectives
Maximum CPU utilization
Maximum throughput
Minimum waiting time
Minimum turnaround time
Minimum response time
Fairness
24. Scheduling Criteria
CPU Utilization
Percentage of time CPU is busy.
Throughput
Number of processes completed per unit time.
Turnaround Time
Turnaround Time = Completion Time − Arrival Time
Waiting Time
Waiting Time = Turnaround Time − Burst Time
Response Time
Response Time = First CPU Start Time − Arrival Time
25. FCFS Scheduling
First Come First Served (FCFS) executes processes according to their arrival order.
Features
Simple
Non-preemptive
Easy to implement
Disadvantage
It may suffer from the convoy effect.
26. SJF Scheduling
Shortest Job First (SJF) selects the process with the smallest CPU burst time.
Advantage
SJF gives the minimum average waiting time under the standard assumptions for a known set of jobs.
Disadvantage
Long processes may experience starvation.
27. SRTF Scheduling
Shortest Remaining Time First (SRTF) is the preemptive version of SJF.
The process with the shortest remaining CPU time gets the CPU.
28. Priority Scheduling
Each process is assigned a priority.
The highest-priority process is selected according to the scheduling convention being used.
It can be:
Preemptive
Non-preemptive
Problem
Low-priority processes may suffer from starvation.
Solution
Aging gradually increases the priority of waiting processes.
29. Round Robin Scheduling
Round Robin is commonly used in time-sharing systems.
Each process receives a fixed time quantum.
If the process does not finish within the quantum, it is moved to the end of the ready queue.
Important
Round Robin is generally preemptive.
30. Scheduling Algorithm Comparison
| Algorithm | Preemptive? | Key Idea |
|---|---|---|
| FCFS | No | Arrival order |
| SJF | No | Shortest burst |
| SRTF | Yes | Shortest remaining time |
| Priority | Both | Priority |
| Round Robin | Yes | Time quantum |
31. Process Synchronization
When multiple processes or threads access shared data, synchronization is required to prevent inconsistent results.
Important Concepts
Critical Section
Race Condition
Mutex
Semaphore
Monitor
32. Critical Section
A critical section is the part of a program where shared data or resources are accessed.
A correct solution should satisfy:
Mutual Exclusion
Progress
Bounded Waiting
33. Race Condition
A race condition occurs when multiple processes/threads access shared data concurrently and the final result depends on the timing or order of execution.
Example
Two threads simultaneously update the same bank balance.
Without synchronization, the final value may be incorrect.
34. Mutex
A mutex is a mutual-exclusion lock used to protect shared resources.
Only one thread can hold a particular mutex at a time.
35. Semaphore
A semaphore is a synchronization mechanism represented by an integer variable and accessed through atomic operations such as:
wait()
signal()
Types
Binary Semaphore
Counting Semaphore
Binary Semaphore
Usually has values:
0 or 1
Counting Semaphore
Can represent multiple available instances of a resource.
36. Deadlock
A deadlock occurs when a set of processes becomes permanently blocked because each process is waiting for a resource held by another process in the set.
Four Necessary Conditions
Deadlock requires all four:
Mutual Exclusion
Hold and Wait
No Preemption
Circular Wait
Memory Trick
M-H-N-C
37. Deadlock Prevention
Deadlock prevention ensures that at least one necessary condition cannot hold.
For example:
Eliminate hold and wait
Allow resource preemption where possible
Impose an ordering on resource acquisition
38. Deadlock Avoidance
Deadlock avoidance dynamically checks resource allocation decisions to ensure the system remains in a safe state.
Famous Algorithm
Banker's Algorithm
39. Deadlock Detection
In deadlock detection, the OS allows resource allocation and periodically checks whether a deadlock has occurred.
If detected, recovery techniques may be applied.
40. Deadlock Recovery
Possible recovery methods include:
Process termination
Resource preemption
Rollback
41. Memory Management
Memory management is the process of managing RAM allocation and deallocation for processes.
Functions
Allocation
Deallocation
Protection
Address translation
Sharing
Virtual memory management
42. Logical and Physical Address
Logical Address
Address generated by the CPU.
Physical Address
Actual address in main memory.
The Memory Management Unit (MMU) translates logical addresses into physical addresses.
43. Contiguous Memory Allocation
In contiguous allocation, a process is assigned a continuous block of memory.
Two common approaches:
Fixed partitioning
Variable partitioning
44. Fragmentation
Internal Fragmentation
Unused space inside an allocated memory block.
External Fragmentation
Free memory exists, but it is divided into small non-contiguous blocks.
45. Memory Allocation Strategies
First Fit
Allocates the first suitable free block.
Best Fit
Allocates the smallest suitable free block.
Worst Fit
Allocates the largest suitable free block.
46. Paging
Paging divides:
Logical memory into pages
Physical memory into frames
Pages and frames have the same fixed size.
Advantages
Eliminates external fragmentation
Makes non-contiguous allocation possible
Disadvantage
Paging can cause internal fragmentation.
47. Page Table
A page table maps:
Page Number → Frame Number
It is used to translate logical addresses into physical addresses.
48. Translation Lookaside Buffer (TLB)
TLB is a fast associative cache that stores recently used page-table entries.
Purpose
To reduce the time required for address translation.
49. Segmentation
Segmentation divides a program into logical variable-sized units such as:
Code
Data
Stack
Functions/modules
Unlike paging, segments are generally variable-sized.
Segmentation can suffer from external fragmentation.
50. Virtual Memory
Virtual memory allows a process to execute even when the entire process is not loaded into physical RAM.
It uses secondary storage as an extension of memory.
Benefits
Allows larger programs to run
Better multiprogramming
Efficient memory use
51. Demand Paging
In demand paging, a page is loaded into memory only when it is needed.
If the required page is not in memory, a page fault occurs.
52. Page Fault
A page fault occurs when a process references a page that is not currently present in physical memory.
General Steps
CPU references a page.
Page is not in memory.
Hardware generates a page-fault trap.
OS checks whether the reference is valid.
Required page is brought from secondary storage.
Page table is updated.
Instruction is restarted.
53. Page Replacement Algorithms
When memory is full and a new page must be loaded, the OS may need to replace an existing page.
Important algorithms:
FIFO
Optimal
LRU
54. FIFO Page Replacement
First-In First-Out replaces the page that has been in memory the longest.
Advantage
Simple to implement.
Disadvantage
May suffer from Belady's Anomaly.
55. Optimal Page Replacement
Optimal replacement removes the page that will not be used for the longest period in the future.
Important
It gives the minimum possible number of page faults for a given reference string and number of frames.
Problem
Future references cannot be known exactly in a real system.
Therefore, it is mainly used as a theoretical benchmark.
56. LRU Page Replacement
Least Recently Used replaces the page that has not been used for the longest time in the past.
It is based on recent usage history.
57. Thrashing
Thrashing occurs when a system spends excessive time handling page faults and swapping pages rather than performing useful computation.
Cause
Usually insufficient memory combined with excessive demand for pages.
Result
CPU utilization may fall dramatically.
58. Swapping
Swapping involves moving processes between main memory and secondary storage.
Purpose
To free memory and support process execution.
59. File System
A file system organizes and manages files on storage devices.
It handles:
File creation
File deletion
Reading
Writing
Naming
Directory organization
Permissions
Examples:
NTFS
FAT32
ext4
APFS
60. File Attributes
Common file attributes include:
Name
Type
Size
Location
Protection
Creation/modification information
61. File Operations
Common file operations:
Create
Open
Read
Write
Seek
Close
Delete
Truncate
62. Directory Structures
Common directory structures:
Single-Level Directory
Two-Level Directory
Tree-Structured Directory
Acyclic-Graph Directory
General Graph Directory
63. I/O Management
The OS manages input/output devices and coordinates communication between software and hardware.
Examples:
Keyboard
Mouse
Printer
Disk
Network interface
64. Device Drivers
A device driver is software that allows the operating system to communicate with a particular hardware device.
Examples:
Printer driver
Graphics driver
Network driver
65. DMA
Direct Memory Access (DMA) allows an I/O device or controller to transfer data directly between the device and main memory with minimal CPU involvement.
Advantage
It reduces CPU overhead for large data transfers.
66. Interrupt
An interrupt is a signal that causes the CPU to temporarily stop its current execution and handle an event through an appropriate interrupt service routine.
Examples:
Keyboard input
I/O completion
Hardware events
67. Interrupt vs Polling
| Interrupt | Polling |
|---|---|
| Device signals CPU | CPU repeatedly checks device |
| More event-driven | Repeated checking |
| Can reduce unnecessary checking | Can waste CPU time |
| Useful for asynchronous events | Simple to implement |
68. Protection and Security
Operating systems provide mechanisms to protect:
Processes
Files
Memory
Devices
User accounts
Common mechanisms include:
Authentication
Authorization
Access control
File permissions
User privileges
69. User Mode and Kernel Mode
Modern operating systems commonly use different privilege levels.
User Mode
Applications run with restricted privileges.
Kernel Mode
The OS kernel runs with higher privileges and can access protected hardware/resources.
A system call provides a controlled transition from user mode to kernel mode.
70. Booting
Booting is the process of starting a computer and loading the operating system.
Basic Process
Power On
↓
Firmware
↓
Bootloader
↓
Operating System Kernel
↓
System Ready
71. Important OS One-Liners for Exams
OS is system software.
Kernel is the core of an OS.
A process is a program in execution.
PCB stores process-related information.
Thread is a basic unit of CPU execution within a process.
FCFS is generally non-preemptive.
Round Robin uses a time quantum.
SRTF is the preemptive form of SJF.
SJF can minimize average waiting time under standard assumptions.
Aging helps prevent starvation.
Deadlock has four necessary conditions.
Banker's Algorithm is used for deadlock avoidance.
Paging divides memory into pages and frames.
Page table maps pages to frames.
TLB speeds up address translation.
FIFO may suffer from Belady's anomaly.
LRU means Least Recently Used.
Optimal replacement uses future reference information.
A page fault occurs when a required page is absent from RAM.
Excessive paging can cause thrashing.
MMU performs address translation.
DMA reduces CPU involvement in data transfer.
Semaphore is used for synchronization.
Mutex provides mutual exclusion.
Critical section accesses shared resources.
Race condition occurs due to unsynchronized concurrent access.
Internal fragmentation occurs inside allocated blocks.
External fragmentation occurs between allocated blocks.
Virtual memory allows execution without loading the entire process into RAM.
A device driver allows OS software to communicate with hardware.
72. Important Differences
Process vs Thread
| Process | Thread |
|---|---|
| Independent execution unit | Execution unit within process |
| Has its own address space | Threads share process address space |
| Higher creation/switching overhead | Usually lower overhead |
| More isolated | Less isolated |
Paging vs Segmentation
| Paging | Segmentation |
|---|---|
| Fixed-size pages | Variable-size segments |
| Physical memory uses frames | Logical units such as code/data |
| No external fragmentation | Can have external fragmentation |
| May have internal fragmentation | Less naturally associated with internal fragmentation |
Deadlock vs Starvation
| Deadlock | Starvation |
|---|---|
| Processes wait indefinitely for each other/resources | A process waits indefinitely because resources/CPU keep going to others |
| Circular waiting may occur | May occur due to unfair scheduling |
| System can become stuck | Other processes may continue |
| Prevention/avoidance/recovery used | Aging can help in scheduling |
73. 50 Important Operating System MCQs
Q1. An operating system is:
A. Application software
B. System software
C. Utility hardware
D. Programming language
Answer: B
Q2. The core component of an operating system is:
A. Shell
B. Kernel
C. Compiler
D. Browser
Answer: B
Q3. A program in execution is called:
A. File
B. Process
C. Instruction
D. Thread only
Answer: B
Q4. Which structure stores information about a process?
A. FAT
B. PCB
C. TLB
D. ALU
Answer: B
Q5. PCB stands for:
A. Process Control Block
B. Program Control Bus
C. Process Computer Block
D. Primary Control Block
Answer: A
Q6. Which is a process state?
A. Ready
B. Running
C. Waiting
D. All of these
Answer: D
Q7. Which scheduling algorithm follows arrival order?
A. SJF
B. FCFS
C. Round Robin
D. SRTF
Answer: B
Q8. FCFS is generally:
A. Preemptive
B. Non-preemptive
C. Both only
D. Neither
Answer: B
Q9. SJF selects the process with:
A. Highest priority
B. Shortest CPU burst
C. Longest CPU burst
D. Earliest deadline
Answer: B
Q10. SRTF is:
A. Non-preemptive FCFS
B. Preemptive SJF
C. Preemptive FCFS
D. Non-preemptive Round Robin
Answer: B
Q11. Round Robin scheduling uses:
A. Priority number
B. Time quantum
C. File size
D. Page size
Answer: B
Q12. Which scheduling algorithm is commonly associated with time-sharing?
A. FCFS
B. Round Robin
C. SJF only
D. FIFO page replacement
Answer: B
Q13. Aging is used to reduce:
A. Deadlock
B. Starvation
C. Fragmentation
D. Thrashing
Answer: B
Q14. A critical section is related to:
A. File compression
B. Shared resource access
C. Disk formatting
D. Booting
Answer: B
Q15. Which condition occurs when the result depends on timing of concurrent operations?
A. Race condition
B. Deadlock only
C. Thrashing
D. Paging
Answer: A
Q16. Which is used for process synchronization?
A. Semaphore
B. Compiler
C. Loader
D. Assembler
Answer: A
Q17. A binary semaphore generally has values:
A. 0 and 1
B. 1 and 2
C. 0 to 10
D. Any negative number only
Answer: A
Q18. Which is NOT a necessary condition for deadlock?
A. Mutual exclusion
B. Hold and wait
C. Circular wait
D. Compilation
Answer: D
Q19. How many necessary conditions are associated with deadlock?
A. 2
B. 3
C. 4
D. 5
Answer: C
Q20. Banker's Algorithm is used for:
A. CPU scheduling
B. Deadlock avoidance
C. File management
D. Disk formatting
Answer: B
Q21. A logical address is generated by:
A. CPU
B. Printer
C. Hard disk
D. Keyboard
Answer: A
Q22. Which hardware component translates logical addresses to physical addresses?
A. ALU
B. MMU
C. CU
D. DMA only
Answer: B
Q23. Paging divides logical memory into:
A. Frames
B. Pages
C. Segments only
D. Blocks only
Answer: B
Q24. Physical memory is divided into:
A. Pages
B. Frames
C. Segments
D. Files
Answer: B
Q25. A page table maps:
A. Frames to files
B. Pages to frames
C. Files to processes
D. CPU to disk
Answer: B
Q26. TLB is used to speed up:
A. File deletion
B. Address translation
C. CPU arithmetic
D. Booting
Answer: B
Q27. Which technique divides memory into variable-sized logical units?
A. Paging
B. Segmentation
C. Fixed partitioning
D. Swapping
Answer: B
Q28. Internal fragmentation occurs:
A. Inside allocated memory blocks
B. Only on hard disks
C. Outside all memory blocks
D. Only in files
Answer: A
Q29. External fragmentation refers to:
A. Unused space inside an allocated block
B. Scattered free memory between allocated blocks
C. CPU idle time
D. Disk failure
Answer: B
Q30. Which allocation strategy selects the first suitable free block?
A. Best Fit
B. First Fit
C. Worst Fit
D. Optimal Fit
Answer: B
Q31. Which strategy selects the smallest suitable free block?
A. First Fit
B. Best Fit
C. Worst Fit
D. FIFO
Answer: B
Q32. Which strategy selects the largest suitable free block?
A. Best Fit
B. First Fit
C. Worst Fit
D. LRU
Answer: C
Q33. Virtual memory allows:
A. Only small programs to execute
B. Programs larger than physical RAM to execute, subject to system limits
C. CPU to work without memory
D. Files to become processors
Answer: B
Q34. A page fault occurs when:
A. CPU fails
B. Required page is not in physical memory
C. File is deleted
D. Process terminates
Answer: B
Q35. Which page replacement algorithm may exhibit Belady's anomaly?
A. FIFO
B. LRU
C. Optimal
D. SJF
Answer: A
Q36. LRU stands for:
A. Last Recently Used
B. Least Recently Used
C. Least Resource Used
D. Longest Recently Used
Answer: B
Q37. Optimal page replacement replaces the page:
A. Used most recently
B. That will not be used for the longest time in the future
C. Loaded first
D. With the smallest number
Answer: B
Q38. Excessive page faults can cause:
A. Starvation only
B. Thrashing
C. Compilation
D. Encryption
Answer: B
Q39. DMA stands for:
A. Direct Memory Access
B. Dynamic Memory Allocation
C. Data Memory Address
D. Direct Machine Algorithm
Answer: A
Q40. DMA primarily reduces:
A. Memory size
B. CPU involvement in certain data transfers
C. File size
D. Number of processes
Answer: B
Q41. Which software allows an OS to communicate with hardware devices?
A. Device driver
B. Compiler
C. Browser
D. Spreadsheet
Answer: A
Q42. A system call provides an interface between:
A. Application and OS kernel
B. Monitor and keyboard only
C. RAM and ROM only
D. Printer and scanner only
Answer: A
Q43. Which mode has greater privileges?
A. User mode
B. Kernel mode
C. Application mode
D. Browser mode
Answer: B
Q44. A shell primarily provides:
A. User interface to the OS
B. Physical memory
C. CPU registers
D. Cache memory
Answer: A
Q45. Which OS type is designed for strict timing constraints?
A. Batch OS
B. Real-Time OS
C. Network OS only
D. Desktop OS only
Answer: B
Q46. Which operating system feature allows multiple programs to remain in memory?
A. Multiprogramming
B. Formatting
C. Compilation
D. Encryption
Answer: A
Q47. A thread generally has its own:
A. Stack
B. Entire process address space
C. All process resources independently
D. Disk partition
Answer: A
Q48. Context switching means:
A. Changing the operating system
B. Saving and restoring execution state when switching processes/threads
C. Formatting memory
D. Changing a file extension
Answer: B
Q49. Which OS function manages files and directories?
A. File management
B. Process scheduling
C. CPU arithmetic
D. Compilation
Answer: A
Q50. Which of the following is an example of an operating system?
A. Linux
B. MS Word
C. Photoshop
D. Google Chrome
Answer: A
Most Important Topics for Bihar STET & BPSC
For exam preparation, give highest priority to:
Very High Priority
Process and Process States
PCB
Threads
CPU Scheduling
FCFS
SJF
SRTF
Priority Scheduling
Round Robin
Synchronization
Critical Section
Race Condition
Semaphore
Mutex
Deadlock
Banker's Algorithm
Memory Management
Paging
Segmentation
Virtual Memory
Page Fault
FIFO
LRU
Optimal Page Replacement
Belady's Anomaly
Thrashing
High Priority
OS Types
Kernel
Shell
System Calls
File Systems
Directory Structures
I/O Management
DMA
Interrupts
Device Drivers
Protection and Security
Quick Memory Tricks
CPU Scheduling
F-S-S-P-R
F = FCFS
S = SJF
S = SRTF
P = Priority
R = Round Robin
Deadlock Conditions
M-H-N-C
M = Mutual Exclusion
H = Hold and Wait
N = No Preemption
C = Circular Wait
Page Replacement
F-L-O
F = FIFO
L = LRU
O = Optimal
Memory Management
P-S-V
P = Paging
S = Segmentation
V = Virtual Memory
Final Revision
Remember these highly important facts:
OS = Resource Manager
Process = Program in Execution
PCB = Process Information
Round Robin = Time Quantum
SRTF = Preemptive SJF
Aging = Reduces Starvation
Banker's Algorithm = Deadlock Avoidance
Paging = Pages + Frames
TLB = Faster Address Translation
FIFO = May Show Belady's Anomaly
LRU = Least Recently Used
Page Fault = Required Page Not in RAM
Thrashing = Excessive Paging
DMA = Direct Memory Access
Kernel = Core of Operating System
These concepts are particularly important for solving Bihar STET and BPSC Computer Science MCQs.
