Telegraphon wire recording device for magnetic audio recording

In the 1890s, the Danish inventor Valdemar Poulsen discovered you could save sounds and signals on magnetizable storage media. From this he developed the first wire recording device, and applied for a patent for it in 1898. At the Paris World Fair in 1900, Poulsen's wire-tone recorders, named "Telegraphones", were a sensation. All of today's magnetic recording methods, including hard drives and magnetic strips on credit cards, are possible thanks to Poulsen's invention.