Two of the most well-known inventors of the late 19th and early 20th centuries, Nikola Tesla and Thomas Edison, were bitter rivals with fundamentally dissimilar ideas about the future of electrical power.

Direct current (DC) electrical systems, which Edison helped create and popularize, were championed by him. In contrast to the alternating current (AC) systems that Tesla and others were promoting, in his opinion, direct current (DC) systems were safer and more dependable. As a major investor in the advancement of DC technology and the owner of several DC power plants, Edison had a personal stake in the promotion of DC systems.

Tesla, on the other hand, thought that AC technology was the best available. AC systems were more efficient and economical than DC systems because they could transmit electrical power across great distances. Tesla was a strong proponent of the use of AC systems in electrical power transmission and had created a number of significant AC-related technologies, such as the AC motor and transformer.

In the latter half of the 1880s and the beginning of the 1890s, there was a "War of Currents" that culminated Tesla and Edison's rivalry. In an effort to prove the purported dangers of AC technology, Edison initiated a campaign to debunk it and promote DC systems, even going so far as to publicly electrocute animals. Tesla, on the other hand, put forth a lot of effort to advance AC technology and create new AC-related technologies.
In the end, Tesla's AC technology triumphed over Edison's DC technology, and AC systems came to be used as the norm for the transmission of electrical power globally. But the rivalry between Tesla and Edison left a lasting impression, and historians, scientists, and inventors are still researching and debating it today.

Despite having different approaches to invention, both Tesla and Edison had a tremendous impact on modern technology. Their rivalry served as a demonstration of the force of competition and the value of creativity in improving civilization.