Credit: ccarlstead CC-BY 2.0. Playing cards developed their four-suit design in the 1480s in France. By the late 1800s, factories mass-produced standard English playing cards that featured diamonds, hearts, clubs and spades, a design that prevails as of September 2014. Older cards were based on Latin suits of cups, swords, coins and rods.
Definition - What does Spread Spectrum mean? Spread spectrum is a technique used for transmitting radio or telecommunications signals. The term refers to the practice of spreading the transmitted signal to occupy the frequency spectrum available for transmission.
Hedy Lamarr developed spread spectrum and frequency hopping technology, which is incorporated in modern Bluetooth technology and essential for Adaptive Frequency Hopping, which is what makes Bluetooth a good-neighbor technology and limits interference. Read this article on Wikipedia for the whole story.