C Introduction

1. What is C?

C is a general-purpose, procedural programming language developed in the early 1970s by Dennis Ritchie at Bell Labs. It is one of the most widely used programming languages, especially in system programming (like operating systems, compilers, embedded systems).

• Procedural means it follows a step-by-step approach using functions.

• General-purpose means it can be used to develop a wide variety of applications.

2. History of C

1. 1969-1972: Developed by Dennis Ritchie at Bell Labs as an improvement over the B language.

2. 1978: First official book “The C Programming Language” by Brian Kernighan and Dennis Ritchie.

3. 1989: ANSI standardized C (called ANSI C).

4. 1990s onward: ISO standardization, leading to C89, C99, C11, and C18 versions.

3. Features of C

C is popular because of its powerful and flexible features:

1. Simple and Structured: Easy to understand and follow a logical sequence.

2. Fast Execution: Low-level capabilities allow fast program execution.

3. Portable: Can run on different machines with minimal modification.

4. Rich Library: Standard library functions for I/O, math, string handling, etc.

5. Memory Management: Allows direct manipulation of memory using pointers.

6. Modular Programming: Supports functions for breaking a program into small parts.

4. Structure of a C Program

A basic C program looks like this:

Explanation:

• #include <stdio.h> – Includes standard input/output library.

• int main() – Entry point of every C program.

• printf() – Function to print output to the screen.

• return 0; – Ends the program successfully.

5. Applications of C

C is widely used in:

1. System Programming: Operating systems, compilers, interpreters.

2. Embedded Systems: Microcontrollers and IoT devices.

3. Game Development: High-performance games.

4. Databases: Backend programming for databases.

5. Desktop Applications: Software like Word processors, spreadsheets.

6. Networking: Developing network drivers and protocols.

6. Advantages of C

• High performance and efficiency.

• Portable across platforms.

• Provides low-level access to memory.

• Foundation for learning other languages like C++, Java, and Python.

7. Disadvantages of C

• No built-in garbage collection (manual memory management needed).

• No object-oriented programming features (like classes).

• Vulnerable to errors like buffer overflow.

8. Why Learn C?

C forms the foundation of modern programming languages. Understanding C gives you:

• Strong problem-solving skills.

• Knowledge of memory management.

• Ability to understand low-level computer workings.

• Easy transition to other languages like C++, Java, and Python.