Linux

GNU GNU not Unix

GNU core utils

X windows:X windows X org

command line interfce:CLI

Shell Libc SystemCall

shell(用C写的)BASH bourne again shell
libc:实现了系统调用的wrapper接口，方便用户使用
system call:

Kernel

kernerl: momory(virtual memory swap space),process,filesystem(VFS ext3),hardware(drive code)

terminal

dumb terminal:
1 graphics capacibility
2 keyboard

查看终端
echo $TERM
infocmp VT100

stty -a
line discipline