BCS Cheat Sheet 2026

The 30 highest-yield BCS facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is the output of the following binary addition: 1011 + 0110? → 10001
2. In computer networks, what is the difference between a hub and a switch? → A hub broadcasts to all ports; a switch forwards to specific ports using MAC addresses
3. What is the purpose of unit testing? → Testing individual components or functions in isolation to verify they work correctly
4. What data structure is typically used to implement Breadth-First Search (BFS)? → Queue
5. Which HTTP status code indicates that a requested resource was permanently moved? → 301 Moved Permanently
6. Which of the following is a typical prerequisite before taking a Data Structures course in a BCS program? → Introduction to Programming
7. What is the purpose of a foreign key in a relational database? → To enforce referential integrity between tables
8. In graph theory, which algorithm finds the shortest path between all pairs of vertices? → Floyd-Warshall Algorithm
9. What is the purpose of normalization in database design? → To reduce data redundancy and improve data integrity
10. How many ways can 5 distinct books be arranged on a shelf? → 120
11. Which graduate-level path most directly extends a BCS degree for someone interested in academic research? → Master of Science or Ph.D. in Computer Science
12. Which protocol operates at the Network layer and is used to report error conditions? → ICMP
13. What is the well-known port number for HTTPS? → 443
14. Which computing concept describes the minimum number of steps required to solve a problem regardless of the algorithm used? → Lower bound complexity
15. What is a zombie process? → A process that has finished execution but still has an entry in the process table
16. In the context of OS, what is a semaphore? → A synchronization primitive used to control access to shared resources
17. Which machine learning technique is used when labeled training data is unavailable? → Unsupervised Learning
18. In software engineering, what is the purpose of the 'Agile' development methodology? → To deliver working software incrementally through iterative development
19. In TCP/IP networking, what is the function of ARP (Address Resolution Protocol)? → Mapping IP addresses to MAC addresses
20. A student choosing between a BCS and a Bachelor of Information Technology (BIT) should know that a BCS typically places greater emphasis on: → Theoretical foundations and algorithm design
21. Which sorting algorithm has a guaranteed O(n log n) time complexity in all cases? → MergeSort
22. Which data structure would be most efficient for implementing a priority queue? → Heap
23. Which sorting algorithm has the best average-case time complexity? → Merge Sort
24. Dynamic programming is best used when a problem exhibits which two properties? → Overlapping subproblems and optimal substructure
25. In graph theory, what is a Hamiltonian path? → A path that visits every vertex exactly once
26. In a relational database, which normal form eliminates transitive dependencies? → Third Normal Form (3NF)
27. What is context switching in an operating system? → Saving the state of a running process and restoring the state of another process
28. What is the maximum transmission unit (MTU) for a standard Ethernet frame? → 1500 bytes
29. In computer networks, what does CIDR notation '/24' indicate in an IP address like 192.168.1.0/24? → The first 24 bits are the network portion
30. Which principle of secure software design states that a user should only have access to what is strictly necessary for their tasks? → Least Privilege