Core CS Subjects

What you will be able to do

• Answer common OS, DBMS and networks questions

What you will learn

1. 7.1Operating Systems9 lessons

   Revise the OS concepts asked in technical interviews, explained with simple examples.

   1. Processes, threads, process states and context switching40 min
   2. CPU scheduling: FCFS and SJF45 min
   3. CPU scheduling: Round Robin, priority and multilevel queues45 min
   4. Synchronisation, critical sections and semaphores45 min
   5. Deadlock: conditions, prevention and avoidance50 min
   6. Memory management: paging and segmentation50 min
   7. Virtual memory and page replacement algorithms50 min
   8. File systems and basic Linux concepts45 min
   9. Practice: OS rapid-fire and numericals60 min
2. 7.2DBMS9 lessons

   Revise database theory for interviews, building on SQL if you have studied it.

   1. DBMS vs file system and types of keys45 min
   2. ER diagrams45 min
   3. Normalisation: functional dependencies, 1NF and 2NF50 min
   4. Normalisation: 3NF and BCNF50 min
   5. ACID properties, transactions and concurrency50 min
   6. Indexing basics45 min
   7. SQL vs NoSQL at a high level40 min
   8. Classic SQL interview queries55 min
   9. Practice: DBMS mixed round and SQL drill60 min
3. 7.3Computer Networks8 lessons

   Explain how data moves across a network at the level placement interviews expect.

   1. OSI and TCP/IP models35 min
   2. IP addresses and subnetting basics45 min
   3. MAC addresses, ARP, DHCP and NAT40 min
   4. TCP vs UDP and the three-way handshake40 min
   5. DNS and what happens when you type a URL45 min
   6. HTTP vs HTTPS, ports and common protocols40 min
   7. Routers, switches and basic network security45 min
   8. Practice: networks rapid-fire and subnetting drill50 min