Process model
The BlackBerry 10 OS architecture consists of the QNX Neutrino microkernel and some number of cooperating processes. These processes communicate with each other via various forms of interprocess communication (IPC). Message passing is the primary form of IPC in BlackBerry 10 OS.
Some definitions
Different operating systems often have different meanings for terms such as "process,""thread,""task,""program," and so on.
Priorities and scheduling
Although there's a good discussion of priorities and scheduling policies in the System Architecture manual, it will help to go over that topic here in the context of a programmer's guide.
Scheduling policies
To meet the needs of various applications, BlackBerry 10 OS provides these scheduling policies:
Why threads?
Now that we know more about priorities, we can talk about why you might want to use threads. We saw many good reasons for breaking things up into separate processes, but what's the purpose of a multithreaded process?
Summary
The modular architecture is apparent throughout the entire system: the BlackBerry 10 OS itself consists of a set of cooperating processes, as does an application.