What are Rust channels for message passing?

Rust follows the message-passing concurrency model with channels. The standard library provides std::sync::mpsc (multi-producer, single-consumer): let (tx, rx) = mpsc::channel();. Multiple senders can clone tx and send values; the single receiver calls rx.recv() (blocking) or rx.try_recv(). The channel is typed — only values of the specified type can be sent. For async code, Tokio provides tokio::sync::mpsc (multi-producer single-consumer), tokio::sync::broadcast (multi-producer multi-consumer, all receivers get every message), and tokio::sync::oneshot (sends exactly one value). Channels enforce the principle that data has a single owner: sending a value moves ownership into the channel, and the receiver takes ownership — preventing data races without locks.