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Learn C Programming

Start from what a program really is, then variables, decisions and loops, on to arrays, pointers and memory.

Lessons
144
Modules out
18 of 18
Parts
5

Who can read what

Free · 47
Anyone can read it, signed in or not.
Free with an account · 59
Free to read once you have an account.
Pro · 38
Included with this track or with Learn Pro.

What is inside

18 modules in 5 parts, 18 of them out so far. Lessons with no mark are free to read.

Part Zero

Before you write a single line

2 modules · 15 lessons

    1. What Programming Really IsReading
    2. Why Learn C When AI Can Write CodeReading
    3. The Story of C: From a Back Room at Bell Labs to Your PhoneReading
    4. Compiler, Interpreter, and What Happens When You Press RunReading
    5. Where C Runs Today: Six Systems You Already UseReading
    6. Structured and Object Oriented: Two Ways to Organise a ProgramReading
    7. Module Test: Before You Write a Single LineModule test

    1. Your First C Program, Line by LineReading
    2. Syntax and Semantics: Two Different Kinds of WrongReading
    3. The Symbol Dictionary: Every Sign in C and What It SaysReading
    4. The Complete ASCII Table, All 128 RowsReading
    5. Comments, Whitespace and Code a Human Can ReadReading
    6. Compile and Run It Yourself: the Playground and a Local ToolchainReading
    7. Problems: First ProgramsProblems
    8. Module Test: Meet CModule test

Part One

The language, piece by piece

3 modules · 22 lessons

    1. Variables: Named Boxes in MemoryReading
    2. Integer Types, Their Ranges, and OverflowReading
    3. Floating Point: float, double, and Why 0.1 Is Not 0.1Reading
    4. char, bool, and the Types That Are Really NumbersReading
    5. sizeof and limits.h: Asking the Machine Instead of GuessingReading
    6. Problems: Variables and TypesProblems
    7. Module Test: Variables and Data TypesModule test

    1. Constants and Literals: Values With a NameReading
    2. const and volatile: Promises You Make to the CompilerReading
    3. printf: Format Specifiers, Width and PrecisionReading
    4. scanf: Reading Input Without Losing Your MindReading
    5. When Input Goes Wrong: Checking What You ReadReading
    6. Problems: Reading and PrintingProblems
    7. Module Test: Constants, Input and OutputModule test

    1. Arithmetic, Integer Division and the Modulo TrapReading
    2. Relational and Logical Operators, and Short CircuitReading
    3. Assignment Shortcuts, ++ and --Reading
    4. Bitwise Operators: Working One Bit at a TimeReading
    5. Precedence and Associativity: When to Reach for BracketsReading
    6. Type Conversion: Promotion, Casting and Silent LossReading
    7. Problems: Expressions That BiteProblems
    8. Module Test: OperatorsModule test

Part Two

Control, functions and recursion

4 modules · 31 lessons

    1. if, else if, else: Choosing a PathReading
    2. Nested Conditions and the Dangling elseFree with an accountReading
    3. switch, case and Fall ThroughFree with an accountReading
    4. The Ternary Operator, and Conditions Worth NamingFree with an accountReading
    5. Under the Hood: How a Branch Becomes a JumpProReading
    6. Problems: DecisionsFree with an accountProblems
    7. Module Test: DecisionsFree with an accountModule test

    1. while: the Idea of RepetitionReading
    2. for: Init, Condition, Update, TracedFree with an accountReading
    3. do while: the Loop That Runs at Least OnceFree with an accountReading
    4. break, continue, and the goto You Will Not UseFree with an accountReading
    5. Nested Loops, Grids and PatternsFree with an accountReading
    6. Thinking in Loops: Sums, Digits, PrimesFree with an accountReading
    7. Bug Gallery: Off by One, Infinite, and the Missing BraceProReading
    8. Problems: LoopsFree with an accountProblems
    9. Module Test: LoopsFree with an accountModule test

    1. Functions: Giving a Piece of Work a NameReading
    2. Parameters, Return Values and PrototypesFree with an accountReading
    3. Pass by Value: What a Function Really GetsFree with an accountReading
    4. Scope: Where a Name LivesFree with an accountReading
    5. Storage Classes: auto, static, extern, registerFree with an accountReading
    6. The Interview Angle: Side Effects, Pure Functions and TestabilityProReading
    7. Problems: FunctionsFree with an accountProblems
    8. Module Test: FunctionsFree with an accountModule test

    1. Recursion: a Function That Calls ItselfReading
    2. The Call Stack, Frame by FrameFree with an accountReading
    3. Recursion Patterns: Factorial, Fibonacci, DigitsFree with an accountReading
    4. Recursion or a Loop: Choosing HonestlyFree with an accountReading
    5. Under the Hood: Stack Frames, Tail Calls and Stack OverflowProReading
    6. Problems: RecursionFree with an accountProblems
    7. Module Test: RecursionFree with an accountModule test

Part Three

Memory and data

6 modules · 55 lessons

    1. Arrays: Many Boxes, One NameReading
    2. Traversal Patterns: Sum, Maximum, CountFree with an accountReading
    3. Searching and Frequency CountingFree with an accountReading
    4. Two Dimensional Arrays and the GridFree with an accountReading
    5. Passing an Array to a FunctionFree with an accountReading
    6. Bug Gallery: Out of Bounds and the Silent WriteProReading
    7. Problems: ArraysFree with an accountProblems
    8. Project: A Marks Report From Raw NumbersProReading
    9. Module Test: ArraysFree with an accountModule test

    1. Characters, ASCII and the char Type in PracticeReading
    2. Strings: an Array That Ends in a ZeroFree with an accountReading
    3. Reading Strings Safely: fgets, and Why gets Was RemovedFree with an accountReading
    4. string.h: strlen, strcpy, strcmp, strcatFree with an accountReading
    5. String Problems: Palindromes, Words, CaseFree with an accountReading
    6. Under the Hood: Where a String Literal Actually LivesProReading
    7. Problems: StringsFree with an accountProblems
    8. Project: A Word Counter That Handles Real TextProReading
    9. Module Test: StringsFree with an accountModule test

    1. Memory and Addresses: Every Box Has a NumberReading
    2. Pointers: a Variable That Holds an AddressFree with an accountReading
    3. Pointers and Arrays: the Same Thing, AlmostFree with an accountReading
    4. Pass by Reference: Letting a Function Change Your VariableFree with an accountReading
    5. Pointer Arithmetic, and const in Three PlacesFree with an accountReading
    6. Function Pointers: Passing Behaviour AroundProReading
    7. Bug Gallery: NULL, Dangling and the Wild PointerProReading
    8. Problems: PointersFree with an accountProblems
    9. Project: Swap, Sort and Search With Pointers OnlyProReading
    10. Module Test: PointersFree with an accountModule test

    1. struct: Grouping Fields That Belong TogetherReading
    2. Arrays of Structs, and Structs in FunctionsFree with an accountReading
    3. Pointers to Structs and the Arrow OperatorFree with an accountReading
    4. typedef, Nested Structs and Organising a ProgramFree with an accountReading
    5. union and enum: When Each One FitsFree with an accountReading
    6. Under the Hood: Padding, Alignment and sizeof SurprisesProReading
    7. Problems: StructuresFree with an accountProblems
    8. Project: A Library Catalogue in MemoryProReading
    9. Module Test: StructuresFree with an accountModule test

    1. Files: Making Data Outlive the ProgramReading
    2. Reading and Writing Text FilesFree with an accountReading
    3. fprintf, fscanf and Formatted File Input and OutputFree with an accountReading
    4. Binary Files, fread and fwriteFree with an accountReading
    5. EOF, Errors, and Closing What You OpenedFree with an accountReading
    6. The Interview Angle: Buffering, Flushing and the Output That VanishedProReading
    7. Problems: FilesFree with an accountProblems
    8. Project: A Log File Reader That ReportsProReading
    9. Module Test: FilesFree with an accountModule test

    1. Why Dynamic Memory: Sizes You Do Not Know YetReading
    2. malloc, calloc, realloc and freeFree with an accountReading
    3. Growing an Array While the Program RunsFree with an accountReading
    4. Structs on the Heap, and a Linked List to FinishFree with an accountReading
    5. Leaks, Double Free, and the Tools That Find ThemFree with an accountReading
    6. Under the Hood: What malloc Actually Asks the Operating SystemProReading
    7. Problems: Dynamic MemoryFree with an accountProblems
    8. Project: A Contact List That Grows on DemandProReading
    9. Module Test: Dynamic MemoryFree with an accountModule test

Part Four

C in the real world

3 modules · 21 lessons

    1. The Preprocessor: What Happens Before the CompilerProReading
    2. Macros: define, Function Macros and Their TrapsProReading
    3. Header Files: Declarations, Guards and What Belongs WhereProReading
    4. Multi File Builds: Compiling, Linking and a First MakefileProReading
    5. Static and Shared Libraries, and Linking Someone Else's CodeProReading
    6. Problems: Building a Program From PartsProProblems
    7. Project: Split One File Into a Real ProjectProReading
    8. Module Test: The Preprocessor and BuildsProModule test

    1. Undefined Behaviour: the Rules You Did Not Know You Were BreakingProReading
    2. Debugging: printf, gdb, Sanitizers and a MethodProReading
    3. Reading Real C: a Walk Through Code From SQLiteProReading
    4. C99 to C23: What Changed, and What You Can Use TodayProReading
    5. Style, Warnings and Writing C That Others TrustProReading
    6. Problems: Find the BugProProblems
    7. Project: Repair a Program That Only Looks CorrectProReading
    8. Module Test: Real World CProModule test

    1. How to Work Like an Engineer: Plan, Build, Test, RepeatProReading
    2. Where to Go After CProReading
    3. Project One: A Text Statistics ToolProReading
    4. Project Two: A Contact Book That Saves to a FileProReading
    5. Project Three: A Tiny Expression InterpreterProReading

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Score is 0 to 1000, across three sections: concepts, read and debug, build.

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  • FoundationRetake400–599
  • WorkingCertificate issued600–749
  • ProficientCertificate issued750–899
  • AdvancedCertificate issued900–1000

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Name
Track
Learn C Programming
Score
/ 1000, with its band
Sections
Concepts · Read and debug · Build
Date, version
What the public page shows. No sample score is printed here on purpose.

Curriculum and chapter plan by Abu Jafar Md Jakaria, based on the author's own lecture notes and teaching materials. Drafted with AI writing tools, then edited and approved by the author.