How to use and when is good use memmove in C?

Question

I have two doubt about use of memmove():

• When is preferable use this function instead of use another function (i.e. a created own functio

Answer 1

When is preferable use this function instead of use another function (i.e. a created own function)

It's faster than a "created own function".

the signature of the function is void *memmove(void *dest, const void *src, size_t n). If I have a simple array arr[N], how can I put it into the called function? arr[N] or &arr[N]

Just arr?