What are ways to allocate memory in C?

// allocate memory of size

void *malloc(size_t size);

//allocates a region of memory, initialized to 0, of size nelements × elementSize

void *calloc(size_t nelements, size_t elementSize);

// resizes allocated memory

void *realloc(void *pointer, size_t size);

// unallocates memory

void free(void *pointer);

Passing non-allocated memory (i.e. not allocated by malloc, calloc, or realloc) to free will result in undefined behavior