The postMessage() method of the MessagePort interface sends a message from the port, and optionally, transfers ownership of objects to other browsing contexts.

API Channel messaging MessagePort Method postMessage Reference

API Client Experimental Method postMessage Reference Service Workers ServiceWorker

The postMessage() method of the DedicatedWorkerGlobalScope interface sends a message to the main thread that spawned it. This accepts a single parameter, which is the data to send to the worker. The data may be any value or JavaScript object handled by the structured clone algorithm, which includes cyclical references.

API DedicatedWorkerGlobalScope Method postMessage Reference Référence Web Workers

The postMessage() method of the Worker interface sends a message to the worker's inner scope. This accepts a single parameter, which is the data to send to the worker. The data may be any value or JavaScript object handled by the structured clone algorithm, which includes cyclical references.

API JavaScript Method postMessage Reference Référence Web Workers Worker