PostMessage
Noun · Development
Definitions
A browser API (window.postMessage) that enables safe cross-origin communication between a page and its iframes, pop-ups, or web workers by sending serialized messages with explicit origin targeting, bypassing the same-origin policy without compromising security.
In plain English: A way for different parts of a webpage — even those loaded from different websites — to safely send messages to each other.
Example: "The embedded payment widget talks to our parent frame via postMessage so we never touch the card data directly."