I have done some simple python programing, but I'm no expert, what I need to do is to comunicate a Raspberry Pi with 12 windows PC's, all of the PC's are connected to UPS do to frequent power shutdowns that I have in my country, the Pi will act as a "server" and it will be monitoring the power source and in the case of a shutdown it will send a command to execute a script on each PC so that they can perform a correct shutdown sequence.
I know how to work with the Pi's GPIO on python, but I have no clue how to communicate then over the LAN.
Any help will be appreciated.