| Single return value | Multiple return values | |
|---|---|---|
| Pull/Synchronous/Interactive | T | IEnumerable<T> | 
| Push/Asynchronous/Reactive | Task<T> | IObservable<T> | 
         
        Geoffrey Huntley Sydney, Australia  | 
      
         
        Claire Novotny New York, USA  | 
      
         
        David Karnok Budapest, Hungary  | 
      
         
        Daniel C. Weber Aachen, Germany  |