From process scheduling and CPU algorithms to MS-DOS commands, Linux/Unix internals, and Windows administration — every topic the BCI 2026 paper asks about, broken down into 7 chapters and 49 microtopics with English + Hindi lessons.
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Syllabus & chapters
Aligned to the official RSSB BCI 2026 syllabus. Each chapter has 7 microtopics with English and Hindi lessons, 10 MCQs per microtopic, 4 spaced-repetition flashcards per microtopic, and a 15-question chapter mock test.
Chapter 1
7 microtopics · 70 MCQs · 28 flashcards
OS Fundamentals
- What an OS Does · OS as Resource Manager + Extended Machine · Boot Sequence
- OS Services — Program Execution · I/O · File Mgmt · Communication · Error Handling · Resource Allocation · Protection · Accounting
- Types of OS — Batch · Multiprogramming · Time-Sharing · Multitasking · Multiprocessing · Distributed · Network · Real-Time (Hard/Soft) · Embedded · Mobile
- OS Structure — Monolithic · Layered · Microkernel · Modular · Hybrid (Linux · Windows NT · macOS XNU · MINIX)
- System Calls — Categories (Process · File · Device · Info · Communication) · API vs Interface · Trap Mechanism
- Kernel Mode vs User Mode · Privileged Instructions · Dual-Mode Operation · Spooling · Buffering vs Caching
- Recap + BCI Full Forms (POSIX · BIOS · RTOS · OS · GUI · CLI · RAM/ROM · PCB) + Comparison Summary
Chapter 2
7 microtopics · 70 MCQs · 28 flashcards
Process Management
- Process Concept · PCB (Process Control Block) · Process States (5-State + 7-State with Suspended) · State Transitions
- Process Creation — fork() · exec() · wait() · exit() · Zombie + Orphan Processes
- Context Switching · Dispatcher · Schedulers (Long-Term · Short-Term · Medium-Term/Swapper) · Context-Switch Overhead
- Threads — User-Level vs Kernel-Level · Many-to-One · One-to-One · Many-to-Many · pthreads · Java Threads · Process vs Thread
- Inter-Process Communication (IPC) — Shared Memory · Message Passing · Pipes (Anonymous / Named) · Sockets · Signals
- CPU Scheduling — Criteria (CPU Util · Throughput · Turnaround · Waiting · Response) · Preemptive vs Non-Preemptive · Convoy Effect · Starvation vs Aging
- Scheduling Algorithms — FCFS · SJF · SRTF · Priority · Round Robin · MLQ · MLFQ — Names + Properties + Worked Gantt [SCI-level]
Chapter 3
7 microtopics · 70 MCQs · 28 flashcards
Process Synchronization
- Race Conditions · Critical Section Problem · Three Requirements (Mutual Exclusion · Progress · Bounded Waiting)
- Software Solutions — Peterson's Algorithm · (mention: Dekker's · Bakery)
- Hardware Solutions — Test-and-Set · Compare-and-Swap · Disabling Interrupts
- Semaphores — Binary vs Counting · wait()/signal() · Busy-Wait vs Blocking · Mutex vs Semaphore
- Monitors — Structure · Condition Variables · wait()/signal() (Hoare vs Mesa) · Java synchronized
- Classic Problems — Producer-Consumer · Readers-Writers · Dining Philosophers · Sleeping Barber (with Semaphore Pseudocode)
- Priority Inversion · Practical Primitives (mutex · spinlock · RW-lock · futex · pthread cond) + Recap
Chapter 4
7 microtopics · 70 MCQs · 28 flashcards
Deadlocks
- Deadlock Concept · Resource-Allocation Graph · Coffman's 4 Necessary Conditions (Mutual Exclusion · Hold-and-Wait · No Preemption · Circular Wait)
- Deadlock Prevention — Break Each of the 4 Conditions · Trade-offs
- Deadlock Avoidance — Safe State · Resource-Allocation Graph Algorithm (Single Instance)
- Banker's Algorithm — Available · Max · Allocation · Need = Max − Allocation · Safety Algorithm · Resource-Request Algorithm · Worked Example [SCI-level]
- Deadlock Detection — Wait-for Graph · Detection Algorithm for Multiple Instances
- Deadlock Recovery — Process Termination · Resource Preemption · Rollback + Checkpointing
- Recap + Ostrich Algorithm (Linux / Windows) + Livelock vs Starvation vs Deadlock
Chapter 5
7 microtopics · 70 MCQs · 28 flashcards
Memory Management
- Memory Hierarchy · Address Binding · Logical vs Physical Addresses · MMU
- Contiguous Allocation · Fixed/Variable Partitions · Internal/External Fragmentation · First/Best/Worst Fit · Compaction · Overlays · Swapping · Static vs Dynamic Loading/Linking
- Paging — Page Table · Frame Allocation · TLB · Effective Access Time · Multi-Level Paging · Inverted Page Tables
- Segmentation · Segmentation with Paging · Paging vs Segmentation Comparison
- Virtual Memory — Demand Paging · Page Faults · Page-Fault Service Routine · Effective Access Time with Page-Fault Rate
- Page Replacement Algorithms — FIFO · Optimal · LRU · Second-Chance/Clock · NRU · LFU/MFU · Belady's Anomaly + Worked Reference Strings [SCI-level]
- Frame Allocation · Thrashing · Working-Set Model · Page-Fault Frequency Control · Locality of Reference
Chapter 6
7 microtopics · 70 MCQs · 28 flashcards
File Systems
- File Concept · Attributes · Operations · File Types · Structure · Access Methods (Sequential · Direct · Indexed)
- Directory Structure — Single-Level · Two-Level · Tree · Acyclic Graph · General Graph · Mount/Unmount
- File Allocation Methods — Contiguous · Linked · Indexed (Single-Level · Multi-Level · UNIX Inode with Direct/Indirect Blocks)
- Free-Space Management — Bit Vector · Linked List · Grouping · Counting
- File Systems Compared — FAT16/32 · NTFS · ext2/3/4 · HFS+ · APFS · Journalling · NFS · File Size Limits
- UNIX File Permissions + chmod — rwx Bits · Octal Notation (chmod 755) · chown · chgrp · Special Bits (SUID · SGID · Sticky) · ACLs
- Linux File & Directory Commands — ls/-l/-a/-i · mkdir · rmdir · rm -r · cp · mv · cat · touch · wc · grep · find · tar · gzip — plus DOS equivalents (dir · md · rd · del · copy)
Chapter 7
7 microtopics · 70 MCQs · 28 flashcards
I/O & System Administration
- I/O Hardware — Buses · Controllers · Ports · Polling vs Interrupt-Driven I/O · DMA · Interrupt Handling
- Kernel I/O Subsystem — I/O Scheduling · Buffering · Caching · Spooling · Device-Driver Interface · Character vs Block Devices
- Disk Structure + Disk Scheduling — Platters/Tracks/Sectors · CHS vs LBA · FCFS · SSTF · SCAN · C-SCAN · LOOK · C-LOOK + Worked Head Movement [SCI-level] · RAID 0/1/5/10
- DOS Commands — DIR · CD · MD/MKDIR · RD · DEL · COPY · MOVE · TYPE · CLS · TREE · ATTRIB · XCOPY · FORMAT · Batch Files (AUTOEXEC.BAT, CONFIG.SYS)
- Linux Process & Admin Commands — ps · top · htop · kill · jobs · bg · fg · nice/renice · df · du · free · uname · who · man
- System Init & Booting — BIOS · UEFI · POST · MBR · GRUB · init / systemd · Runlevels · Backup & Restore Basics (tar, rsync)
- Windows vs Linux vs macOS Comparison — Kernel Type · File Systems · Process Model · User/Admin Model · Package Management · BCI Recap
Chapter 8
7 microtopics · 70 MCQs · 28 flashcards
MS-DOS
- MS-DOS Introduction · History · System Files (IO.SYS · MS-DOS.SYS · COMMAND.COM · CONFIG.SYS · AUTOEXEC.BAT)
- DOS Boot Process · Directory Structure · File Naming (8.3) · Wildcards (* and ?)
- Internal Commands — DIR · COPY · TYPE · MD · CD · RD · DEL · REN · CLS · DATE · TIME · VER · VOL · PROMPT · PATH
- External Commands — ATTRIB · CHKDSK · FORMAT · DISKCOPY · XCOPY · TREE · DELTREE · FIND · MORE · SORT · EDIT · HELP
- Redirection (> < >>) · Pipes (|) · I/O Redirection Patterns
- Batch Files (.BAT) · Batch Commands (@ · ECHO · REM · PAUSE · IF · GOTO · CALL · %DIGIT)
- Recap · DOS vs Windows Command Prompt vs PowerShell · DOS in modern systems
Chapter 9
7 microtopics · 70 MCQs · 28 flashcards
Linux & UNIX
- UNIX & Linux Introduction · History (Bell Labs / Linus Torvalds 1991) · Open Source · Distributions (Ubuntu · Fedora · Debian · Mint · CentOS · Red Hat)
- Linux/UNIX Architecture — Kernel · Shell · System Calls · Application Layer · Users
- Linux File System Hierarchy (/ · /bin · /etc · /home · /var · /tmp · /usr · /dev · /proc · /root) · Everything is a File · i-nodes basics
- Basic Commands — pwd · ls · cd · mkdir · rmdir · cp · mv · rm · cat · touch · echo · man · history · clear · who · whoami · date · cal
- File Permissions — rwx · Octal Notation (chmod 755) · chmod · chown · chgrp · Users · Groups · sudo · root
- Process Commands — ps · top · kill · & · fg · bg · jobs · nohup · Pipes (|) · Redirection (> >> <)
- Vi/Vim Editor Basics (modes · save/quit) · Shell Scripting Fundamentals · Recap
Chapter 10
6 microtopics · 60 MCQs · 24 flashcards
Windows OS
- Windows History · Version Timeline (Windows 1.x · 95 · 98 · 2000 · XP · Vista · 7 · 8 · 8.1 · 10 · 11) · Key Features per Version
- Windows Architecture — NT Kernel · HAL · Subsystems · Win32 API · GUI Layer (light overview)
- Windows GUI Components — Desktop · Taskbar · Start Menu · System Tray · File Explorer · Control Panel · Settings · Windows Shortcuts
- Windows Utilities — Task Manager · Device Manager · Disk Management · MMC · Registry Editor · Run Dialog · Command Prompt · PowerShell · MSCONFIG
- Windows File Systems — FAT · FAT16 · FAT32 · NTFS · exFAT · ReFS · Drive Letters · UNC Paths
- System Tools · Disk Cleanup · Defragmenter · Backup & Restore · Windows Update · Recap
Chapter 11
7 microtopics · 70 MCQs · 28 flashcards
CPU Organization
- Register Transfer Language (RTL) · Notation
- Bus Organization · 3-State Buffers · Memory Transfer
- Arithmetic Microoperations · Adder-Subtractor · Incrementer
- Logic Microoperations · Shift Microoperations · ALSU Design
- Basic Computer Registers · Common Bus System
- Instruction Formats (3-, 2-, 1-, 0-address) · Set Completeness
- Instruction Cycle — Fetch · Decode · Execute · recap
Chapter 12
7 microtopics · 70 MCQs · 28 flashcards
Addressing Modes & Control Unit
- Addressing Modes — Immediate · Direct · Indirect · Register
- Indexed · Base-Register · Relative · Auto-Inc/Dec addressing
- Memory-Reference vs Register-Reference vs I/O Instructions
- Hardwired Control Unit — Design · Control Logic Gates
- Microprogrammed Control — Control Memory · Address Sequencing
- Microinstruction Format · Microprogram Sequencer
- Hardwired vs Microprogrammed — Comparison · recap
Chapter 13
7 microtopics · 70 MCQs · 28 flashcards
Memory Hierarchy & I/O
- Memory Hierarchy — Register · Cache · Main · Secondary
- RAM (SRAM vs DRAM) · ROM Types (PROM/EPROM/EEPROM/Flash)
- Cache Mapping — Direct · Associative · Set-Associative
- Cache Write Policies — Write-through · Write-back · Replacement
- Virtual Memory — Pages · TLB · Page Replacement
- I/O Modes — Programmed · Interrupt-driven · DMA
- Priority Interrupts · Daisy-chain · Parallel Priority · recap
Chapter 14
7 microtopics · 70 MCQs · 28 flashcards
Pipelining & Architecture
- Parallel Processing — Flynn's Taxonomy (SISD/SIMD/MISD/MIMD)
- Pipelining Concept · Speedup · Efficiency Formulas
- Arithmetic Pipeline vs Instruction Pipeline
- Pipeline Hazards — Structural · Data · Control · Stalls/Forwarding
- RISC vs CISC Characteristics · Trade-offs
- RISC Pipeline (3-segment) · Delayed Load · Delayed Branch
- Vector / Array Processors · Multiprocessor intro · recap
How MeritPrep helps you crack Operating Systems
- Microtopic depth: Each concept is broken into a 5-minute focused lesson with worked examples and diagrams, not 50-page chapters.
- RSSB pattern MCQs: Every MCQ is written in the style of past Paper II questions, with detailed explanations.
- Spaced repetition: Flashcards enter your Daily Review queue with intervals tuned to keep concepts fresh through exam day.
- Mock tests: 15-Q chapter mocks plus full-syllabus mocks for Operating Systems when you're ready.
- Bilingual: Every lesson is available in both English and Hindi.
Frequently asked questions
Is Operating Systems content free to read?
Chapter 1 of this subject is fully free, and the entire DBMS subject is free. To unlock the rest of Operating Systems and every other BCI subject, get BCI Full Access for ₹1,499 — valid through 22 August 2026 (BCI Paper II exam day).
How does this prepare me for the BCI 2026 exam?
The Operating Systems chapters mirror the official BCI Paper II syllabus exactly. Past-year questions (PYQs) are tagged on relevant MCQs so you know which topics are highest-yield. The combination of focused microtopic lessons, RSSB-pattern practice, and spaced repetition is designed for the exam format.
Is content available in Hindi?
Yes — every lesson, MCQ, and flashcard has a Hindi version. Toggle between English and Hindi from the language button at the top of the app.