I'm going to see my Dad this weekend (for the first time in ages)

He's asked me to explain email attachments to him, and I want to sent a variety of file types before I get there.

He uses a Mac and I have no idea of the Mac equivalent to a .exe file.

If anyone can explain that or even better point me towards a nice small self-contained Mac program which I can send him, I'd be most grateful.

I will of course highlight the virus threat.

Many thanks

Ed