Their CPU, their boards, their firmware (presumably), their OS[1], much of the perhipherals are theirs, too.
Lots of companies try to emulate Apple, but it's very hard to pull off.
[1] Yes, they use some parts from Mach and FreeBSD in their OS, but the amalgamation is theirs, and they support and change the whole thing as needed.
Their CPU, their boards, their firmware (presumably), their OS[1], much of the perhipherals are theirs, too.
Lots of companies try to emulate Apple, but it's very hard to pull off.
[1] Yes, they use some parts from Mach and FreeBSD in their OS, but the amalgamation is theirs, and they support and change the whole thing as needed.