cpu/:	Code for cpu stuffs
dm/:	Device Management (char, block, ioctl, etc)
fs/:	Code for VFS, filesystem management, abstraction for files, file handle control, and OCRW
loader/:Code for loading files (modules, ELF executables)
mm/:	Code for the management of memory. vm, pm, heap, paging, etc
tm/:	Code for process management, switching, fork/exit, signals, and IPC
./:		General kernel files