1️⃣ DSA (Data Structures & Algorithms) Interviewers test problem-solving, logic, and complexity analysis. Common topics include arrays, strings, hash maps, stacks, queues, recursion, greedy, and dynamic programming. They focus more on approach, edge cases, and time/space complexity than writing perfect code. 2️⃣ OOPS OOPS questions check design thinking. Core concepts include encapsulation, inheritance, polymorphism, abstraction, virtual functions, and friend classes. Interviewers expect clarity on compile-time vs runtime polymorphism and real-world usage rather than definitions only. 3️⃣ One SQL Query Usually a practical query like finding top N records, duplicates, latest records, joins, or aggregation. They check correct use of JOIN, GROUP BY, HAVING, ORDER BY, LIMIT, and handling of NULLs with clean logic and explanation. 4️⃣ Project-Related Question They ask deep questions about your project: why you chose an approach, challenges faced, how you handled errors, optimized performance, and what you’d improve if scaling. They want ownership, not memorized answers.