The use of the available technology to transfer information and data dates
back thousands of years. The earliest examples include signal fires and
smoke signals. More recently, technologies emerged to make use of electrical
currents to transfer data include Morse’s telegraph, Marconi’s wireless, and
licensed radio stations. While the use of wireless technologies for communications
and information transfer was a hallmark of the 20th century, wireless
data communications protocols such as infrared, Bluetooth, RFID, and Wi-Fi
have become an essential component of modern computing devices. While
all are used to transfer data, each of these technologies differs in protocol,
coverage range and performance.