An Actor is not a sequential process because it does not have a program counter that moves sequentially through a program.

You might find Actors more intuitive. For example, see the following video by Hewitt, Meijer and Szyperski: The Actor Model (everything you wanted to know, but were afraid to ask)

https://channel9.msdn.com/Shows/Going+Deep/Hewitt-Meijer-and...