Guglielmo Marconi was an Italian inventor and electrical engineer who is best known for his pioneering work in the development of long-distance radio transmission. He is credited with inventing the first practical system of radio communication and was awarded the Nobel Prize in Physics in 1909 for his contributions to the development of wireless telegraphy. Marconi's work laid the foundation for modern wireless communication and he is considered one of the key figures in the history of telecommunications.