"C++ isn't cross platform"

[Fried Chicken]

As my C++ book tells me C++ programs can only be used on the specific CPU and OS you compiled it on but yet I made a few programs and sent them around to my friends and they work fine >.<

[1vRz3TCk]

If you compile your program to run on say Windows and send the program to me it will not run on my Mac but probably would run on my Windows PC.

[Fried Chicken]

Yes but it states that it can only run on the specific CPU that you compiled it on, as for the OS thing that's just common knowledge.

[Athar]

Not the CPU you compiled it for, but the CPU architecture you compiled it for.
On PCs, x86 and x86_64 are the relevant architectures.

[Fried Chicken]

So as long as they're running Windows it's compatible?

[Athar]

Most likely (if you compiled for x86 (aka 32-bit)). Although I heard Windows 7 supports ARM now (or is supposed to sometime in the future), so your program wouldn't run on an ARM machine, even if it runs Windows.