There are 5 stable (non-experimental) marker traits as of Rust 1.88.0 (2025-07-30):

Marker TraitDescription
CopyCan be Cloned by using bitwise copy.
Use #[derive(Copy)] to generate an impl of Copy
Sendcan be transferred across thread boundaries.
SizedConstant size known at compile time.
SyncSafe to share references between threads.
(i.e., &T is Send)
UnpinDon’t require any pinning guarantees.
Can be moved after it was pinned

Notes