# How to write SOS Morse Code using CyberPi
Morse code is an early digital communication method. It contains dots ("·" referred to as short signals) and dashes ("—", referred to as long signals), short spaces between dots and dashes, and long spaces between characters. This # How to guide describes how to write Morse code and decode it using block-based programming.
SOS is an international distress signal. In Morse code, "S" is coded as three dots and "O" as three dashes. So SOS is made up of "· · · — — — · · ·". You can compile it to send a distress signal.
How to write Morse code and decode it using block-based programming?
Variables and Blocks You Need to Create for the Program