Rust uses fat-pointers to references and raw pointers to dynamically sized types (DSTs) – slices or trait objects. A fat pointer contains a pointer plus some in

Rust uses fat-pointers to references and raw pointers to dynamically sized types (DSTs) – slices or trait objects. A fat pointer contains a pointer plus some information that makes the DST "complete" (e.g. the length, or in the case of trait objects, the additional data is a pointer to the vtable). Generally, you have, under control, where you store your fat-pointer.