Course content (32 lessons)

1. About This Course — Programming using 'C' Language — University Course This course provides a thorough introduction to the C programming language as taught in undergraduate university courses. The…
2. Unit 1 — History and Features of C — History and Features of C Origin of C C was developed by Dennis Ritchie at Bell Labs between 1969 and 1973 . It grew out of the B language (itself derived from BCPL) and was first…
3. Unit 1 — Data Types and Variables — Data Types and Variables in C What is a Data Type? A data type specifies the type of data a variable can hold, the amount of memory it occupies, and the operations that can be…
4. Unit 1 — Operators in C — Operators in C An operator is a symbol that tells the compiler to perform a specific operation on operands. --- Categories of Operators 1. Arithmetic Operators Operator Meaning…
5. Unit 1 — Input and Output in C — Input and Output in C C handles I/O through the stdio.h (Standard Input/Output) library. --- printf() — Formatted Output Format specifiers: Specifier Type Example -----------…
6. Unit 1 — Control Structures — Control Structures in C Control structures determine the flow of execution of a program. --- 1. if Statement 2. if-else Statement 3. if-else-if Ladder 4. Nested if --- 5. switch…
7. Unit 1 — Jump Statements — Jump Statements in C Jump statements transfer control to another part of the program, breaking the normal sequential flow. --- 1. break Exits the nearest enclosing loop or switch…
8. Unit 2 — Functions: Definition and Calling — Functions in C — Basics A function is a self-contained block of code that performs a specific task. Functions make programs modular, reusable, and easier to debug. --- Types of…
9. Unit 2 — Recursion — Recursion in C Recursion is a technique where a function calls itself to solve a problem. Every recursive function must have: 1. A base case — condition to stop recursion 2. A…
10. Unit 2 — Preprocessor Directives — Preprocessor Directives in C The C Preprocessor processes source code before compilation . Directives start with and are not C statements (no semicolon needed). --- 1. include…
11. Unit 2 — Storage Classes — Storage Classes in C A storage class defines the scope (visibility), lifetime (duration), and default initial value of a variable. --- The Four Storage Classes 1. auto - Default…
12. Unit 2 — Arrays in C — Arrays in C An array is a collection of elements of the same data type stored in contiguous memory locations, accessed using an index. --- 1. One-Dimensional Arrays Declaration:…
13. Unit 2 — Pointers in C — Pointers in C A pointer is a variable that stores the memory address of another variable. --- Pointer Basics Operators: - & (address-of) — gives the address of a variable -…
14. Unit 3 — Structures — Structures in C A structure is a user-defined data type that groups variables of different data types under a single name. Each variable in a structure is called a member . ---…
15. Unit 3 — Unions — Unions in C A union is a user-defined data type similar to a structure, but all members share the same memory location . The size of a union is equal to the size of its largest…
16. Unit 3 — Enums and Typedef — Enums and Typedef in C Enumeration (enum) An enum is a user-defined data type consisting of named integer constants. It improves code readability. Syntax: Example: Custom values:…
17. Unit 3 — File Handling — File Handling in C File handling allows C programs to read from and write to files on disk, enabling permanent data storage. --- File Pointer All file operations use a FILE…
18. Unit 4 — Standard Library: stdio.h — Standard Library: stdio.h The stdio.h (Standard Input/Output) header provides functions for reading and writing data to streams (console, files). --- Console I/O Functions…
19. Unit 4 — Standard Library: stdlib.h — Standard Library: stdlib.h The stdlib.h header provides general-purpose functions for memory management, type conversions, random numbers, and program control. --- Memory…
20. Unit 4 — Standard Library: string.h — Standard Library: string.h The string.h header provides functions for manipulating C strings (null-terminated character arrays). --- String Length --- String Copy --- String…
21. Unit 4 — Standard Library: math.h — Standard Library: math.h The math.h header provides mathematical functions. Compile with -lm flag on Linux/GCC. --- Basic Functions Function Description Example ----------…
22. Unit 4 — Standard Library: ctype.h — Standard Library: ctype.h The ctype.h header provides functions for character classification and conversion . All functions take an int (character value) as argument. ---…
23. Unit 4 — Command-Line Arguments — Command-Line Arguments in C C programs can accept arguments from the command line using argc and argv parameters of the main function. --- Syntax Parameter Description -----------…
24. Unit 4 — Standard Library: time.h — Standard Library: time.h The time.h header provides functions for working with dates and times . --- Key Types Type Description ------ ------------- time t Integer type…
25. Unit 1 — Type Conversion and Casting — Type Conversion and Casting in C In C, values of one data type can be converted to another. There are two kinds of conversions: implicit (automatic) and explicit (casting). ---…
26. Unit 1 — Loop Patterns and Nested Loops — Loop Patterns and Nested Loops in C Nested loops are loops placed inside other loops. They are commonly used for working with 2D data and printing patterns. --- Nested Loop Syntax…
27. Unit 1 — Scope and Lifetime of Variables — Scope and Lifetime of Variables in C Scope determines where a variable can be accessed. Lifetime determines how long a variable exists in memory. --- Types of Scope 1. Block Scope…
28. Unit 2 — Function Pointers and Advanced Pointers — Function Pointers and Advanced Pointers in C Function Pointers A function pointer stores the address of a function and allows calling it indirectly. Syntax: Example: --- Array of…
29. Unit 2 — Dynamic Memory Allocation — Dynamic Memory Allocation in C Dynamic memory allocation allows programs to request memory at run time rather than compile time. This is managed using functions from stdlib.h .…
30. Unit 3 — Bit Fields and Miscellaneous — Bit Fields in C Structures A bit field is a member of a structure that occupies a specified number of bits rather than full bytes. Bit fields are used to save memory when storing…
31. Unit 4 — Error Handling in C — Error Handling in C C does not have built-in exception handling like C++ or Java. Instead, error handling is done through return values , errno , and error-reporting functions.…
32. Previous Year Questions — C Language — Previous Year Questions PYQ papers for this course will be added here soon. Check back later for: - End Term Examination papers - Mid Term papers - Important…

Unit 1 — History and Features of C

History and Features of C

Origin of C

C was developed by Dennis Ritchie at Bell Labs between 1969 and 1973. It grew out of the B language (itself derived from BCPL) and was first used to rewrite the UNIX operating system.

Timeline:

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Why Learn C?

• C is a middle-level language — it has features of both high-level and low-level languages.
• It is the foundation of many modern languages (C++, Java, Python runtime is in C).
• Used in operating systems, embedded systems, compilers, and more.

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Features of C

1. Simple — easy to learn with a small set of keywords (32 in C89).
2. Portable — programs can run on different hardware with minimal changes.
3. Fast — compiled language with direct memory access.
4. Structured — supports functions and modular programming.
5. Rich Library — vast standard library for I/O, string handling, math.
6. Pointers — direct memory manipulation via pointers.
7. Extensible — you can add your own functions to the library.

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Structure of a C Program

/* Documentation Section */
#include <stdio.h>       /* Preprocessor Directive */

int main() {             /* Main Function */
    printf("Hello, World!\n");
    return 0;
}

Sections of a C program:

• Documentation — comments explaining the program
• Preprocessor directives — #include, #define
• Global declarations — variables/functions accessible everywhere
• main() — entry point of every C program
• User-defined functions — additional functions

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Compilation Process

1. Source Code (.c file) → Preprocessor → Expanded Source
2. Expanded Source → Compiler → Assembly Code
3. Assembly Code → Assembler → Object Code (.obj)
4. Object Code + Libraries → Linker → Executable (.exe)

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