In plain words: Calling an LWC method from a Visualforce page allows legacy Visualforce layouts to trigger actions inside modern Lightning Web Components. Because Visualforce and LWC run on different runtime engines, communication is handled on the client side using Lightning Out with public @api methods or by publishing events across the platform using Lightning Message Service (LMS) . During digital transformation projects, organizations rarely replace entire Visualforce applications overnight. Instead, developers embed modern Lightning Web Components inside existing Visualforce pages. To make these hybrid pages interactive, your Visualforce JavaScript must be able to invoke functions and pass data directly into the hosted LWC.
Topic
LWC
Lightning Web Components