Windows 8 Target commands?

[GTXPlayer]

So, I decided to experiment with my game programs with target commands, to learn a little about what each does.

However I am unsure about a few things, and I'm looking for some answers. Here they are:

Are there a list of global target commands?

Do all Target commands work with all programs, or are they limited to a specific program, and built into the program, and not overridden by Windows?

Thanks.