Avoid using `commercial' as a synonym for `non-free'
(see http://www.gnu.org/philosophy/words-to-avoid.html#Commercial).
Make a clear distinction between kernels and Operating Systems
(Linux is a kernel, FreeBSD and NetBSD are Operating Systems, Mach
is a microkernel, VSTa is something in-between).
Use 64-bit types to describe 64-bit datum (instead of splitting in
two 32-bit fields). Little endianess assumption applies (as per
Terminology section).