Tasks and activities for this website?

So activities are not the same as tasks, but how would they differ for a website such as TripAdvisor? Like what would be an activity and what would be a task? For example, you have the option to find hotels but you cannot book hotels from TripAdvisor directly. If however that was possible, it would be more clear to me that an activity would be the process of finding and booking a hotel room and the tasks were the individual parts (i.e. the finding and booking separately). This is not the case, so what are tasks and what are activities then?

Another example of activities and tasks: Spotify facilitates the activity of enjoying music with all the needed tasks such as browsing, filtering, making playlists, etc.