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In C, the switch statement evaluates an expression and executes the matching case when the expression equals that case’s value. If no cases match, the default case is executed. This allows for handling different conditions clearly and efficiently to make your code easier to read compared to multiple if-else statements. In this lesson, I will explain how to use a switch case statement in C.

In C programming, the if statement is a control structure that allows conditional execution of code blocks based on boolean expressions. It enables programs to make decisions by evaluating conditions, executing specific code when conditions are true, and optionally handling alternative scenarios with else or else if. Proper use of if statements enhance program logic and flow control.

In C programming, reserved keywords are predefined identifiers with specific meanings, such as int, return, and if. They form the language’s core syntax, enabling the compiler to understand and execute code correctly. Using these keywords appropriately ensures proper program structure, prevents naming conflicts, and maintains code readability and functionality. You should not use them as names of variables or functions in your code. This article gives a comprehensive list of reserved keywords in C and their meaning.

Variables in C are essential storage locations identified by unique names, holding data of specific types such as int, float, or char. They can have different scopes—local, global, or static—determining their accessibility and lifetime. Proper declaration and initialization are crucial for effective memory management, enabling efficient data manipulation and ensuring reliable, maintainable code. This lesson guides you through the correct use of variables in C.

Structures in C allow you to group variables of different types under a single name, enabling the creation of complex data models. To use structures, define them with the struct keyword, declare structure variables, initialize their members, and access members using the dot (.) operator. This organization enhances code readability, maintainability, and effectively models real-world entities. This lesson helps you understand the use of structures in C.

C data types are categorized into primary types—such as void, char, int, float, and double—that represent fundamental values. Derived types like arrays, pointers, structures, and unions build upon these basics to create complex data structures. Additionally, user-defined types, including enums and typedefs, allow programmers to create customized and readable code, enhancing flexibility and efficiency in memory management and program design. In this guide, I will walk you through the use of different data types in C.

The main function in C serves as the entry point of the program, where task execution begins. It is typically defined with an int return type and can accept command-line arguments through parameters like argc and argv[]. Within its body, the main function contains the core logic of the program and ultimately returns an integer to indicate the program’s exit status. In this guide, we will learn the structure and the best practices to follow when writing your first main C program.

A C program begins with preprocessor directives to include necessary libraries, defines the main() function as the entry point, declares variables, uses statements and expressions to perform operations, incorporates functions for modularity, and includes comments for clarity. It ends with a return statement which signals a successful execution. In this lesson, we will learn the basic structure of a C program.

Setting up a C development environment involves installing a compiler like GCC via MinGW-w64 on Windows, Homebrew on macOS, or your distro's package manager on Linux. In this article, I will walk you through the necessary steps to install the required compiler to run a C program. We will also look at some of the best text editors you can use to write your code. By the end of this lesson, you will be able to know how to install a C compiler.

C has numerous advantages, including portability, efficiency, low-level hardware control, a rich standard library, and structured programming, enabling high performance and flexibility. Its ability to manipulate memory directly and support for recursion makes it ideal for system programming, embedded systems, and applications requiring optimized performance. In addition, it has a widespread user community. This lesson takes a detailed look into the features of the C programming language.

C remains foundational across a vast range of contemporary computing. It powers the kernels of major operating systems like Linux and Windows, enabling fine-grained control over hardware. Embedded systems—from automotive ECUs to IoT devices—rely on C for efficient, real-time operation within strict resource constraints. This article gives a detailed overview of the use of C.