Free and open to everyone

Learn it properly, then prove it.

Full courses taught idea first, then traced by hand, then coded — with a step-through simulator in almost every lesson that you drive yourself. No account, no payment, no autoplay.

2 courses65 lessons~31 hrNo sign-up needed
FreeBeginnerIntermediateAdvanced

DSA: Zero to Placement Ready

A complete Data Structures and Algorithms track for engineering students, assuming no prior coding at all. It starts at writing your first program and ends at defending your approach in an interview. Every topic is taught idea first, then traced by hand on a small example, then coded naive and optimised, and closes with the interview questions and practice problems that topic actually attracts.

11
Modules
38
Lessons
~20 hr
Material
Start the first lesson
  1. 1

    Getting Started with Code

    Beginner4 lessons

    Your first program, the types your data lives in, the operators that combine it, and the branching that makes it decide.

  2. 2

    Loops and Pattern Printing

    Beginner2 lessons

    Repetition, dry running with trace tables as a graded skill, and the i-j reasoning gymnasium that everything later depends on.

  3. 3

    Functions and Data Containers

    Beginner5 lessons

    Naming and reusing code, then the containers you will spend the rest of the course filling: arrays, strings, matrices and the standard library.

  4. 4

    Complexity and Math

    Beginner2 lessons

    How to count what your code costs before you run it, and the number theory that shows up in interview problems.

  5. 5

    Recursion and Bits

    Intermediate2 lessons

    The call stack drawn out frame by frame, and the bit operations that turn arithmetic tricks into one-liners.

  6. 6

    Sorting and Searching

    Intermediate4 lessons

    Four algorithms built from scratch and compared honestly on stability, adaptivity and cost - not on reputation.

  7. 7

    Array and String Patterns

    Intermediate4 lessons

    The named patterns interviewers actually test, and the recognition skill that lets you name the right one from the problem statement.

  8. 8

    Linear Data Structures

    Intermediate3 lessons

    Pointer rewiring, the monotonic stack that collapses a quadratic scan to linear, and the queues behind sliding windows and BFS.

  9. 9

    Trees, Heaps and Tries

    Advanced4 lessons

    Non-linear structures: traversals as one recursion with the visit moved, the BST property, the heap array trick, and prefix trees.

  10. 10

    Graphs and Algorithmic Techniques

    Advanced5 lessons

    Traversal on graphs and grids, then the four techniques that solve most hard problems: backtracking, dynamic programming, greedy and the advanced structures.

  11. 11

    Interview Preparation

    Advanced3 lessons

    Core CS revision, the six-step method run end to end on a real problem, and what each company track actually tests.

FreeBeginnerIntermediateAdvanced

DBMS: From Files to Transactions

A complete Database Management Systems course for engineering students, assuming no prior database experience. It starts at the difference between data and information and ends at serialisable schedules, taking in ER modelling, the relational model, SQL and normalisation on the way. Every topic is taught idea first, then shown running on a small concrete example you can step through yourself, then closed with the interview questions and practice that topic actually attracts.

6
Modules
27
Lessons
~12 hr
Material
Start the first lesson
  1. 1

    Foundations of Database Systems

    Beginner3 lessons

    What data, a database and a DBMS actually are, the file-system problems that made database software necessary, and the people who run it.

  2. 2

    DBMS Architecture

    Beginner4 lessons

    The three levels a database is described at, what data independence buys you, schemas versus instances, the four families of database language, and how the tiers are laid out.

  3. 3

    The ER Model

    Intermediate5 lessons

    Modelling a real situation before you build any table: entities, attributes, relationships, cardinality, weak entities, and the extended features of specialisation and aggregation.

  4. 4

    The Relational Model

    Intermediate4 lessons

    Tables done properly: relations and tuples, the full family of keys, the constraints that keep data honest, and the rules for turning an ER diagram into tables.

  5. 5

    SQL

    Advanced6 lessons

    The language itself, from CREATE TABLE to views, with the query evaluation order, grouping, joins and subqueries taught by running them a step at a time.

  6. 6

    Normalization and Transactions

    Advanced5 lessons

    Why a badly designed table corrupts itself, how to decompose it through 1NF to BCNF, and how transactions and schedules keep concurrent work correct.