Found here:
http://docs.angularjs.org/guide/introduction
It states that "You can use Angular to develop both single-page and round-trip apps, but Angular is designed primarily for developing single-page apps. Angular supports browser history, forward and back buttons, and bookmarking in single-page apps."
But I'm not finding much on the two terms, spelled exactly that way, but I did find this: http://en.wikipedia.org/wiki/Round-trip_engineering
Is this the correct term?
Single page app, everything happens on one "page", although the URL might change. Most state changes are shown to the user without going to the server (they'll go to the server for data, but not html/js/css etc)
Round-trip apps are apps that change pages on every get/post/put request. The round trip is the path the application takes from the browser, to the server, to the browser to display every change in state to the user. This usually results in "flicker" as the web browser has to redraw every page.
Round-trip engineering is a different beast.
来源：https://stackoverflow.com/questions/19501553/what-is-the-meaning-of-single-page-apps-in-context-with-round-trip-apps