Electromechanical era

                                                                                      Electronics engineering

Voltaic battery

Invented by Alessandro Volta in 1799. The voltaic pile was the first electrical battery that could continuously provide an electric current to a circuit. 

Telegraph 

It superseded optical semaphore telegraph systems, such as Claude Chappe's towers designed for communication among the French military, and Friedrich Clemens Gerke for the Prussian military, thus becoming the first form of electrical telecommunications.

In 1753 an anonymous writer in the Scots Magazine suggested an electrostatic telegraph. Using one wire for each letter of the alphabet, a message could be transmitted by connecting the wire terminals in turn to an electrostatic machine, and observing the deflection of pith balls at the far end.

Telephone

Antonio Meucci, 1854, constructed telephone-like devices.

The invention of the telephone was the culmination of work done by many individuals, and involved an array of lawsuits founded upon the patent claims of several individuals and numerous companies.

Through failed attempts to use "make-and-break" current, to successful experiments with electromagnetic telephones by Antonio Meucci, Alexander Graham Bell and Thomas Watson, and finally commercially successful telephones in the late 19th century.

Radio

Radio has it's roots in the telegraph, invented by Guglielmo Marconi and patented in 1896 in England. Marconi's telegraph, sending transatlantic messages in Morse code, quickly became a commercial success and the dominant means of wireless marine communication at the beginning of the 20th century.

                                   Electromechanical computing

 Tabulations machines

The tabulating machine was an electromechanical machine designed to assist in summarizing information and, later, accounting. Invented by Herman Hollerith, the machine was developed to help process data for the 1890 U.S. Census. It spawned a class of machines, known as unit record equipment, and the data processing industry.

Comptometer

The comptometer was the first commercially successful key-driven mechanical calculator, patented in the USA by Dorr E. Felt in 1887.

Comptograph

 

A machine for adding numbers and making a printed record of the sum. The original comptometer design was patented by Dorr E. Felt, a citizen of the United States. The first two patents were granted on July 19, 1887 and on October 11, 1887.

punched cards

Herman Hollerith invented the recording of data on a medium that could then be read by a machine. Prior uses of machine readable media, such as those above (other than Korsakov), had been for control, not data. "After some initial trials with paper tape, he settled on punched cards