## Arc https://doc.rust-lang.org/rust-by-example/std/arc.html Arc (Atommically Reference Counted) is used when you want to share ownership between multiple threads. ```rust use std::time::Duration; use std::sync::Arc; use std::thread; fn main() { // This variable declaration is where its value is specified. let apple = Arc::new("the same apple"); for _ in 0..10 { // Here there is no value specification as it is a pointer to a // reference in the memory heap. let apple = Arc::clone(&apple); thread::spawn(move || { // As Arc was used, threads can be spawned using the value allocated // in the Arc variable pointer's location. println!("{:?}", apple); }); } // Make sure all Arc instances are printed from spawned threads. thread::sleep(Duration::from_secs(1)); } ``` ## Box Box is used when you want to allocate a value on the heap rather than the stack.