CS Fundamentals
263 articles in this topic

Sequential circuits: flip-flops, latches and counters explained
Sequential circuits for GATE: SR, D, JK and T flip-flops, excitation tables, latch versus flip-flop, and a fully worked synchronous counter design example.

Combinational circuits: multiplexers, decoders and adders explained
A combinational circuit's output depends only on its current inputs, with no stored state. Multiplexers, decoders, encoders and adders are the blocks GATE keeps testing, and a single 4-to-1 MUX can implement any three-variable Boolean function using just one inverter.

Boolean algebra and K-map minimization: a worked GATE guide
K-map minimization becomes routine once you can read the groupings. Six Boolean identity pairs, DeMorgan's two theorems, the SOP and POS canonical forms, and a four-variable map traced loop by loop from seven minterms and three don't-cares down to F = B' + A'D.

Number systems and base conversions: binary, octal and hexadecimal explained
Number systems for GATE: binary, octal and hexadecimal, base conversion, r's and (r-1)'s complement, signed representation, BCD and Gray code, worked.

B+ Trees and Database Indexing: why indexes are fast, with a worked insert
B+ trees and database indexing explained: dense vs sparse, primary clustering and secondary indexes, B-tree vs B+ tree, with a worked B+ tree insert example.

Process Synchronization and Semaphores: race conditions, Peterson's solution, wait and signal
Process synchronization explained: the race condition, critical-section problem, Peterson's solution, binary and counting semaphores, and a worked trace.

Memory Hierarchy and Virtual Memory: paging, the TLB, and address translation
Memory hierarchy and virtual memory explained: registers to disk, locality, paging, page tables, the TLB, a worked address translation, and access time.

SQL Queries and Joins in DBMS: sublanguages, joins, and GROUP BY worked out
SQL queries and joins in DBMS: DDL DML DCL TCL sublanguages, SELECT and WHERE, inner and outer joins, GROUP BY with HAVING, plus a worked join example.

Transactions and concurrency control in DBMS: ACID, schedules, serializability
Transactions in DBMS explained: ACID properties, schedules, conflict serializability with a worked precedence graph, two-phase locking, and the exam angle.

Normalization in DBMS: 1NF to BCNF, with the exam angle
Normalization in DBMS explained: functional dependencies, the exact 1NF, 2NF, 3NF and BCNF rules, a worked decomposition of one relation, and 3NF vs BCNF.

Pipelining in Computer Architecture: the 5-stage pipeline, speedup, and hazards
Pipelining in computer architecture: the 5-stage pipeline, speedup and throughput formulas, CPI, structural, data and control hazards, and forwarding.

Turing Machines and Decidability: recursive vs RE, and the halting problem
Turing machines and decidability explained: TM definition and configurations, recursive vs recursively enumerable languages, the halting problem, reductions.