BCS Written Computer Science study guide
BCS Written Computer Science · Work through your exam, one topic at a time.
The BCS Written Computer Science examination is a descriptive, essay-style assessment used by the Bangladesh Computer Society (BCS) as part of its professional certification for computer science professionals. It is intended for graduates and practitioners who need to demonstrate a broad, structured understanding of computing rather than narrow coding skill. The BCS Written Computer Science study guide has 10 sections and about 2,650 words.
01Computer Fundamentals and Computer Architecture
Candidates must be fluent in number systems and data representation (binary, octal, hex, two's complement, BCD, ASCII/Unicode), logic gates and Boolean algebra, and the fetch-decode-execute cycle. Know the roles of the program counter, instruction register, memory address register, accumulator, and control unit.
287 words, about 1 min02Data Structures and Algorithms
You must know the behaviour and complexity of arrays, linked lists, stacks, queues, trees (binary search trees, AVL, heaps), hash tables, and graphs. Be able to state average and worst-case time for search, insertion, and deletion, and to explain why a balanced tree gives O(log n) while a degenerate BST degrades to O(n).
309 words, about 2 min03Programming Languages and Software Development
Understand the translation pipeline: source code, lexical analysis, syntax analysis, semantic analysis, intermediate code, optimisation, and code generation, plus the difference between compilers and interpreters. Know programming paradigms (imperative, object-oriented, functional, logic), and OOP principles: encapsulation, inheritance, polymorphism, and abstraction.
246 words, about 1 min04Database Systems and Data Management
Master the relational model: relations, tuples, attributes, keys (primary, candidate, foreign, composite), and integrity constraints (entity and referential). Understand normalization through 1NF, 2NF, 3NF, and BCNF, and the anomalies each removes.
251 words, about 1 min05Computer Networks and Data Communications
Know the OSI seven layers and the TCP/IP model, and map protocols to layers: application (HTTP, FTP, SMTP, DNS), transport (TCP, UDP), internet (IP, ICMP), and link (Ethernet, ARP). Understand addressing: MAC addresses at layer 2, IP addresses and subnetting at layer 3, ports at layer 4.
263 words, about 1 min06Operating Systems and Systems Software
Understand the OS as a resource manager and extended machine: process management, CPU scheduling (FCFS, SJF, priority, round robin), process states and the PCB, context switching, threads versus processes, and inter-process communication. Study synchronization: critical sections, mutexes, semaphores, and deadlock's four necessary conditions (mutual exclusion, hold and wait, no preemption, circular wait).
274 words, about 1 min07Software Engineering and System Analysis and Design
Know the software development life cycle: requirements, analysis, design, implementation, testing, deployment, and maintenance. Compare process models - waterfall, incremental, spiral, prototype, and agile/Scrum - and when each fits.
289 words, about 1 min08Information Security and Cyber Security
Understand the CIA triad (confidentiality, integrity, availability) and supporting concepts such as authentication, authorization, non-repudiation, and accountability. Study symmetric versus asymmetric cryptography, hashing, digital signatures, and public key infrastructure.
234 words, about 1 min09Emerging Technologies and Current Trends in Computing
Be able to explain cloud computing service models (IaaS, PaaS, SaaS) and deployment models (public, private, hybrid, community), plus characteristics such as on-demand self-service and elasticity. Understand virtualization and containers.
252 words, about 1 min10ICT in Governance and Public Sector Applications
Understand e-government and its stages: information, interaction, transaction, and transformation. Know government service delivery models (G2C, G2B, G2G, G2E), digital identity and authentication, and interoperability standards.
245 words, about 1 min