The notification center reference should say (IMHO) thread, not task.
I don't think that's correct. The default notification centre is per-
process, not per-thread, I believe.
Personally I think of a thread as an executable that I can ask to
do different tasks for me, where a task is a job that I need done.
That's even more confusing than the original! And you've thrown the
meaning of executable into question as well, as well as using the
word "job" (which is also ambiguous).
A thread is a separate flow of control, usually with some per-thread
state. A process is a collection of threads and some per-process
state. An executable is a binary image of a program, often held on
disk (e.g. "/bin/ls" is an executable).
The word "task" is sometimes used to mean "process" (in the computing
sense). It is also often used in the normal English sense of the
word (i.e. some work to be done). Which meaning you ascribe to a
particular occurrence of the word depends on the context.
