The Raspberry Pi should always be shut down correctly to avoid the SD card being corrupted (by losing power while performing a write operation to the card). This can pose a problem if you don't have a keyboard or screen connected (you might be running an automated program or controlling it remotely over a network and forget to turn it off) as you can't type the command or see what you are doing. By adding our own buttons and LED indicator, we can easily command a shutdown and reset, and then start up again to indicate when the system is active.