The architecture of unix based os contains three parts majorly they are

  • Hardware
  • Shell
  • Kernel


For example we are saving the file, modifying the file and deleting the file in our system. This means that we are making the changes in the hard disk, but we are not making the changes in the hard disk directly. We are making the changes indirectly.




  • We are giving the commands to the shell.
  • Shell decodes the command to machine understandable language.
  • Those machine understandable commands or decoded commands are sent to the kernel by the shell.
  • The kernel generates the instruction set to the processor.
  • The processor will make the changes directly on hard disk by using the memory.
  • Here memory, processor and the hard disk are the hardware.