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πŸ–₯ Interview Prep

CS Fundamentals

Big-O, memory, processes and threads, operating systems, networking, databases, security and OOP: the theory rounds.

100 questions, most asked first

Ordered so the most useful questions for learning each pattern come first.

#1What's the Big-O of this code?ComplexityEasyFree#2Process vs threadProcesses & threadsEasyFree#3Stack vs heap memoryMemoryEasyFree#4TCP vs UDPNetworkingEasyFree#5The four pillars of OOPOOPEasyFreeUnlock 36 more CS Fundamentals questions Β· all 1,200 questions for $39/year (about 11Β’ a day)See full access#11The OSI and TCP/IP modelsNetworkingEasyπŸ”’#13Compiled vs interpreted languagesComplexityEasyπŸ”’#14Recursion and the call stackMemoryEasyπŸ”’#17Hashing vs encryption vs encodingSecurity & cryptoEasyπŸ”’#19The singleton patternDesign patternsEasyπŸ”’#20The factory patternDesign patternsEasyπŸ”’#21The observer patternDesign patternsEasyπŸ”’#22The strategy patternDesign patternsEasyπŸ”’#24The adapter patternDesign patternsEasyπŸ”’#25Method overloading vs overridingOOPEasyπŸ”’#28Space complexityComplexityEasyπŸ”’#30Concurrency vs parallelismProcesses & threadsEasyπŸ”’#40Sockets and portsNetworkingEasyπŸ”’#41How a CPU runs your codeNumbers & binaryEasyπŸ”’#52Arrays vs linked listsMemoryEasyπŸ”’#54Trees vs graphsComplexityEasyπŸ”’#58Recursion vs iterationMemoryEasyπŸ”’#60Why immutability helpsSOLID & clean codeEasyπŸ”’#63Coupling and cohesionSOLID & clean codeEasyπŸ”’#64DRY, KISS and YAGNISOLID & clean codeEasyπŸ”’#65Common code smellsSOLID & clean codeEasyπŸ”’#66MVC and similar architecturesDesign patternsEasyπŸ”’#73Containers vs virtual machinesOperating systemsEasyπŸ”’#79Latency vs bandwidth vs throughputLatency & cachingEasyπŸ”’#81Checksums and data integritySecurity & cryptoEasyπŸ”’#85Authentication vs authorizationSecurity & cryptoEasyπŸ”’#86Least privilege and defense in depthSecurity & cryptoEasyπŸ”’#90Moore's law and the multicore eraProcesses & threadsEasyπŸ”’#91What does an operating system do?Operating systemsEasyπŸ”’#92What is an API?NetworkingEasyπŸ”’#93How does the internet work (the big picture)?NetworkingEasyπŸ”’#94What is a database, and why not just use files?DatabasesEasyπŸ”’#95Cloud computing basics (IaaS, PaaS, SaaS, serverless)Operating systemsEasyπŸ”’#97CPUs vs GPUsProcesses & threadsEasyπŸ”’#98Procedural vs object-oriented codeOOPEasyπŸ”’#100Open-source licensesSOLID & clean codeEasyπŸ”’