In C, constants and variables are different in terms of their nature and usage. Here are some key differences between constants and variables:
-
Value modification: Constants are values that remain unchanged throughout the program execution, whereas variables can have their values altered during program execution.
-
Declaration and initialization: Constants are typically declared and initialized in a single statement. Once initialized, their values cannot be modified. Variables, on the other hand, can be declared without initialization and assigned values multiple times during program execution.
-
Storage and memory: Constants are usually stored in read-only memory (ROM) or code memory, depending on the platform, and they occupy space in memory. Variables, on the other hand, are stored in mutable memory (RAM) and can occupy different memory locations as their values change.
-
Naming conventions: Constants are commonly named using uppercase letters, underscores, and digits to distinguish them from variables. Variables, in contrast, are usually named using lowercase letters, underscores, and digits.
-
Usage and purpose: Constants are often used to represent fixed values that remain the same throughout the program, such as mathematical constants or configuration settings. They provide a way to assign meaningful names to these values and improve code readability. Variables, on the other hand, are used to store and manipulate values that can change during program execution.
It's important to note that the "const" keyword in C allows you to declare variables as constants, indicating that their values should not be modified after initialization. This helps enforce immutability and can provide additional safety and clarity in code.
