It may not be a useful distinction, but it's useful to have a sense for where on the continuum the thing you're building sits, in order to make technology and architecture decisions. If you're building something more "website-y", it should probably have an architecture that optimizes for search-ability and static caching, whereas if you're building something more "webapp-y", the architecture should probably optimize interactivity and dynamic updates. Most things end up somewhere in the middle, but leaning one way or the other.