Samuel Morse
Since the 1700s, there were different types of telegraphs being made, but they were hard to use because they had several wires. (The first telegraph ever built had 26 wires, which made it almost impossible to use.) Morse spent years trying to build one with only one wire, and managed to do it in 1836. Morse and his assistant made a code with "dots and "dashes", which were two different types of "clicks" on the telegraph.