Functions in C can be categorized based on their purpose, structure, and usage. Here are some common categories of functions:

• Built-in Functions:
  Functions that are part of the C standard library and provide fundamental operations. Examples include printf(), scanf(), and strlen().
• User-Defined Functions:
  Functions created by the programmer to perform specific tasks. These functions enhance code modularity and reusability.
• Recursive Functions:
  Functions that call themselves either directly or indirectly. Recursive functions are often used for solving problems that can be broken down into smaller subproblems.
• Library Functions:
  Functions provided by external libraries to perform specialized tasks. For example, functions from the math library like sin(), cos(), and sqrt().
• Inline Functions:
  Functions defined with the inline keyword. These functions are expanded by the compiler at the point of the function call rather than being called like regular functions.
• Callback Functions:
  Functions that are passed as arguments to other functions. Callback functions allow for greater flexibility and customization in certain scenarios.
• Pointer to Functions:
  Functions whose addresses can be stored in pointers. This enables dynamic selection and invocation of functions at runtime.
• Variadic Functions:
  Functions that can accept a variable number of arguments. Examples include printf() and scanf().
• Constructor and Destructor Functions:
  Functions used in object-oriented programming or resource management. Constructors initialize objects, while destructors clean up resources when an object is no longer needed.
• Getter and Setter Functions:
  Functions that retrieve (get) or modify (set) the values of private variables within a class or structure.

Low Level Language