Keywords in C Programming

Keywords in C are the building blocks of the programming language. These reserved words have predefined meanings and functionalities that the C compiler recognizes. They cannot be used as identifiers, such as variable names or function names, ensuring clarity and consistency in programming.

This post covers all the keywords in C, their significance, and key differences from identifiers. Let’s dive deeper into understanding keywords in C with examples and details.

What Are Keywords in C?

Keywords in C are predefined words with a fixed meaning that the compiler understands. These reserved words cannot be modified or used for any other purpose, ensuring clarity and avoiding ambiguity in the code.

Key Features of Keywords

1. Reserved Words:
   Keywords are predefined and reserved for specific tasks within the C language, ensuring consistent functionality.
2. Case-Sensitive:
   All keywords in C are written in lowercase and are case-sensitive, distinguishing them from user-defined identifiers.
3. Fixed Functionality:
   The meaning and purpose of keywords are fixed by the language and cannot be altered by the programmer.
4. Integral to Syntax:
   Keywords form the foundational elements of C’s syntax, enabling control structures, data types, and program flow.
5. Cannot Be Used as Identifiers:
   Keywords cannot be used as variable names, function names, or any user-defined labels to avoid conflicts in the program.
6. Universal Across Compilers:
   Keywords behave uniformly across all C compilers, maintaining portability and consistency in C programs.

List of Keywords in C

A list of keywords in C or reserved words in the C programming language are mentioned below:

Specific Keywords With Descriptions

Key Properties of Keywords in C

1. Predefined and Reserved:
   Keywords have fixed meanings defined by the C language and cannot be altered.
2. Lowercase Only:
   All keywords in C are case-sensitive and must be written in lowercase.
3. Recognized by Compiler:
   Keywords are processed uniquely by the compiler to perform specific tasks.
4. Not Allowed as Identifiers:
   Keywords cannot be used as variable names, function names, or any other user-defined identifiers.
5. Essential for Syntax:
   Keywords form the foundation of the C programming syntax, enabling control flow, data types, and other features.
6. Universal Across Compilers:
   The meaning and functionality of keywords remain consistent across all C compilers.

Examples of Keywords in Use

Example 1: Control Flow Keywords

#include <stdio.h>  

int main() {  
    int num = 10;  

    // if-else keyword  
    if (num > 5) {  
        printf("Number is greater than 5\n");  
    } else {  
        printf("Number is 5 or less\n");  
    }  

    // for keyword  
    for (int i = 0; i < 5; i++) {  
        printf("Iteration %d\n", i);  
    }  

    return 0;  
}  

Example 2: Data Type Keywords

#include <stdio.h>  

int main() {  
    int integer = 100;          // int keyword  
    char character = 'A';       // char keyword  
    float floating = 10.5;      // float keyword  

    printf("Integer: %d\n", integer);  
    printf("Character: %c\n", character);  
    printf("Floating Point: %.2f\n", floating);  

    return 0;  
}  

Difference Between Keywords and Identifiers

Youtube Links:

Keywords in C are the backbone of the programming language, providing the essential structure and functionality needed to write efficient programs. Mastering keywords is a crucial step in becoming proficient in C programming.

The next post is: Identifiers in C. Stay tuned to explore how identifiers are used in tandem with keywords to write meaningful and functional programs.

FAQs on Keywords in C