The Executive Services, the Hardware Abstraction Layer (HAL), the microkernal, and kernel mode drivers
The shell is made up of several subsystems that all operate in user mode. The kernel, or core, of the OS is responsible for interacting with hardware. It has more power to communicate with hardware devices than the shell has, and operates in kernel mode.
bt.o is the kernel mode driver. When you insmod bt.o you are inserting it into the kernel, where it can cause bad things to happen if it screws up. btduser is the user mode driver. It runs as an application in user space, where usually the worse thing that can happen is a segfault. You don't have to insmod anything for user mode. You just run the application.
what layer is made up of liqid and iron
Ozone Layer
Ozone layer is made up of ozone. It is an allotrope of oxygen.
it is made up of decomposed bits of minerals from the humos layer
The Linux boot process can be divided into six steps which are as follows: # Kernel loader loading, setup, and execution: In this step, the bootsect.s file is loaded into the memory by the BIOS. When the bootsect.s file sets up, it loads the rest of the kernel into the memory. # Parameter setup and switch to 32-bit mode: When the kernel has been loaded, the boot.s file sets up a temporary IDT and GDT and handles the switch to 32-bit mode. # Kernel decompression: The head.s file decompresses the kernel. # Kernel setup: After the kernel is decompressed, the real GDT and IDT are created by the head.s (second file). # Kernel and memory initialization (main.c): In this step, the kernel sets up all memory constraints and virtual memory is completely set up. # Init process creation (main.c): In the final step of booting, the init process is created, which switches a Linux computer to different run levels. Ref: http://www.ucertify.com/article/what-are-the-various-steps-of-the-linux-boot-process.html
The UNIX operating system is made up of three parts; the kernel, the shell and the programs.
the 2nd layer is made up of shorter trees and saplings
A layer of zinc coated with a thin layer of copper.
The second layer
Ozone layer is made of O2 only. It is because ozone is an allotrope of oxygen.