Apple etc. compatibility

[TerryRitchie]

This  is a pretty wide-ranging question, and I guess not many will be interested in answering it. But here goes…
My computer uses Windows 10. I’m only familiar with Windows, and have no access to other systems for testing.
I use a fairly small subset of PE for coding (no DMAs, Peeks or Pokes etc.)
I have a couple of friends with Apple systems and I’d like to share some of my progs with them, but I’m loth
to just hand them a copy and say “try this”, in case it interferes with their settings, or worse.
Are they safe to run on other systems, and will they run similarly to how they run on mine?
And if so, are there sections of PE that still should be avoided for compatibility?  (the .exe files, I mean)
 

You won't be able to just send your compiled .EXE files to them. The .EXE files you create on your system are specifically compiled for Windows. You'll either need to have your friends install QB64 and compile your source code (your .BAS files) or have someone with an Apple compile your source for you to then hand to your friends.

There's no need to worry about your programs interfering with your friend's computer systems unless you specifically wrote the code to do that. Your code will run the same whether it's been compiled on Windows, MacOS, or Linux.

Some QB64 commands do work a bit differently (or not at all) between the three operating systems. Someone that uses an Apple would be better suited however to fill you in on what those difference are.