Mac OS X is built on the XNU (X is Not Unix) kernel which is a hybrid combining elements of the Mach kernel and FreeBSD.
Yes, they are, as cross platform means that it (the TIFF file) can be used by both Macintosh and PC platforms.
There is no real answer to that, because there is no theLinux operating system. There are several different operating systems that use the Linux kernel but incorporate a variety of different software, each varying in size and code complexity. The Linux kernel includes approximately 13.5 million lines of code, although much of this code will not be used in any given binary kernel image, as it is platform or usage-specific.
Linux is a modern operating system kernel used by GNU/Linux systems like Ubuntu, Linux Mint, Debian, OpenSuSe, Fedora and many other. Linux is mainly used for servers and embedded systems, but is gaining popularity in desktop system market.
Mac OS
Mac OS X
No it is RAM memory used by the operating system
Mac OS
It can be. The kernel has a real time process scheduler, and there's a popular real time patchset that is often used to modify the kernel to be a more dedicated real-time system.
basically, if i understand your question, you want to know in plain ol' english what a kernel is. Basically it is just the main part of the operating system that gets information from applications and submits it to hardware for processing. If you want more specific info regarding a kernel, check out the wikipedia page for it.
Mac OS
Not sure what you are asking. The operating system for Macintosh computers is OS X. It is a modified version of UNIX. The processor chips (currently i3, i5 & i7) used in Macintosh computers for some years now are made by Intel, the same chip used in most PCs today.
An operating system is usually defined as a collection of software used to create a complete and usable system. By that definition, he did not create any operating system. Torvalds created the most important piece of an operating system, a kernel. The kernel he created is called Linux.