How is memory freed in C?

In C programming, memory that has been dynamically allocated using functions such as malloc(), calloc(), or realloc() must be explicitly freed to prevent memory leaks. The correct way to do this is by using the free() function.

When you allocate memory dynamically, it is allocated on the heap, which is a region of your computer's memory that is used for dynamic allocation. If you do not free the memory after it is no longer needed, that memory remains allocated and cannot be reused until the program terminates, leading to inefficient memory usage and potentially exhausting available memory for other operations.

The free() function takes a pointer as an argument, which must point to a memory block that was previously allocated. This function deallocates the memory and makes it available for future allocations. It's important to note that after calling free(), the pointer is still defined but points to deallocated memory, which should not be accessed unless reallocated.

Understanding the proper use of the free() function is crucial for effective memory management in C, as it enables developers to handle memory efficiently, optimize resource usage, and maintain program stability.