[ebcode]

>> (And, if there is any other core concept I am missing, I would love to hear that too.)

When you get into parallel programming, I think you'll need more than just those 4. But I'm not sure what the reduction is. Something akin to forking and joining.

[sam_goody]

Of course! There is another one that is really difficult enough to earn it's own pace on the list:

- naming variables.