CS fundamentals
Computer Networks
From the OSI and TCP/IP models to routing, TCP, DNS and HTTP: how data actually moves between machines.
Computer Networks
Neso Academy, 135 videos, English
A layer-by-layer course with clear animations; ideal first pass.
3 picks, in suggested order
More in CS fundamentals
Operating Systems
Processes, threads, scheduling, synchronisation, deadlocks and memory management: the OS questions every SDE interview asks.
Neso Academy, Gate Smashers, Hussein Nasser
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DBMS & SQL
ER models, normalisation, transactions, indexing and SQL, from interview basics to how databases work inside.
Gate Smashers, Rishabh Mishra, Arpit Bhayani, CMU Database Group
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Computer Organisation & Architecture
How a CPU runs your code: instruction formats, pipelining, caches and memory hierarchy.
Neso Academy, Gate Smashers
2 playlists166 videosEnglishHindi
Theory of Computation & Compilers
Automata, regular expressions, grammars and how a compiler turns source code into machine code.
Neso Academy, Gate Smashers
3 playlists148 videosEnglishHindi