Rc is for single-threaded reference counting, while Arc provides thread-safe reference counting for sharing data across threads.
The difference is that Rc is for single-threaded reference counting while Arc is for thread-safe reference counting across multiple threads. Use Rc when data is confined to one thread for better performance, and Arc when you need to share ownership between threads.
use std::rc::Rc;
use std::sync::Arc;
let single_thread = Rc::new(vec![1, 2, 3]);
let multi_thread = Arc::new(vec![1, 2, 3]);
Think of Rc as a counter that tracks how many people are holding a document in a single room, while Arc is a secure counter that works even if people are in different rooms or buildings. You use Rc when everyone is in the same place to save time, and Arc when you need to share that document safely across different parts of your program running at the same time.