Wt is different to templating. It's server side rendering and the widgets communication is transparent, based on slots and receivers in the server side.
If you came from java it has similarities to Vaadin.
You don't have to write JavaScript, and it generates a page that acts like an SPA and does all the AJAXy stuff for you in the background. So you can just say "I want a button that does this server action on click" and it manages all the communication between the browser and the back end. It even gracefully degrades to full page reloads if the user doesn't have JavaScript turned on.
