Electricity and Magnetism — Tech Evolutions

Entry	Year	Description	Impact
1	1800	Alessandro Volta invents the voltaic pile, the first true electric battery. This provided a continuous source of electric current, moving beyond static electricity experiments.	Revolutionized the study of current electricity, enabling systematic experiments on circuits and leading to discoveries like Ohm's Law and the chemical effects of current. Paved the way for practical electrical devices.
2	1820	Hans Christian Ørsted discovers that electric currents produce magnetic fields. This was the first experimental evidence linking electricity and magnetism.	Opened the field of electromagnetism, leading to Ampère's laws, the development of electromagnets, and eventually electric motors. Fundamentally changed the understanding of these forces.
3	1831	Michael Faraday discovers electromagnetic induction, demonstrating that a changing magnetic field can induce an electric current.	The foundational principle for electric generators, transformers, and many other electrical devices. Made large-scale electricity generation and transmission possible, ushering in the electrical age.
4	1860s	James Clerk Maxwell formulates his set of equations, unifying electricity, magnetism, and light into a single theory of electromagnetism.	Provided a complete theoretical framework for electromagnetism, predicted electromagnetic waves, and showed light to be an electromagnetic phenomenon. Basis for all wireless communication and modern physics.
5	Late 19th Century	The 'War of the Currents' between Thomas Edison (DC) and Nikola Tesla/George Westinghouse (AC) culminates in the widespread adoption of Alternating Current (AC) for power distribution.	AC's ability to be easily transformed to different voltages allowed for efficient long-distance power transmission, making centralized power generation and widespread electrification feasible. Shaped modern power grids.