Types of Constants in C

Example: 'A', '5', '@'

String Constants

These represent sequences of characters and are enclosed in double quotes.

Example: "Hello, World!", "C programming"

Symbolic Constants (Using const and #define)

Symbolic constants are named values that make the code more readable and maintainable. They are defined at the beginning of a program and used throughout.

There are two common ways to define symbolic constants:

Using const Keyword

Symbolic constants can be defined using the const keyword, which specifies that a variable's value should not change after initialization.

Using #define Preprocessor Directive

The #define preprocessor directive creates symbolic constants using a macro. They are replaced with their values during preprocessing.

Symbolic constants are preferred when you want to give meaningful names to values, making the code more self-explanatory and easier to maintain. Literal constants, on the other hand, are used when specific values are needed directly in the code.

Enumerated constants

Enumerated constants are constants that are defined by the programmer. Enumerated constants are declared using the enum keyword.

This enum defines seven constants, each representing a day of the week.

Conclusion

Constants in C programming are fixed values that remain unchanged during program execution. They are used to represent unvarying data, such as numerical values, characters, or strings. Constants can be either literal, defined directly in the code, or symbolic, given meaningful names for improved readability and maintainability.