Automatic app download vs automatic app update

In Settings > iTunes & App Store, there is a list section with header title “AUTOMATIC DOWNLOADS”. (I'm not shouting, the title is in all-caps.)

In this section there is an on-off switch for “Apps” and another for “App Updates”. What is the difference? It might be the case that the text below applies only to the last row but that is not clear. And in any case, treating "Automatic downloads for Apps" and "Automatic downloads for App Updates" as different things is pretty severely ambiguous.