In the most basic form, a cell phone is essentially a two-way radio, consisting of a radio transmitter and a radio receiver. When you chat with your friend on your cell phone, your phone converts your voice into an electrical signal, which is then transmitted via radio waves to the nearest cell tower. The network of cell towers then relays the radio wave to your friend’s cell phone, which converts it to an electrical signal and then back to sound again. In the basic form, a cell phone works just like a walkie-talkie.

Martin Cooper (born December 26, 1928) is an American engineer. He is a pioneer and visionary in the wireless communications industry. With eleven patents in the field, he is recognized as an innovator in radio spectrum management. 

While at Motorola Cooper invented the first handheld cellular mobile phone (distinct from the car phone) in 1973 and led the team that developed it and brought it to market in 1983. He is considered the "father of the cell phone" and is also cited as the first person in history to make a handheld cellular phone call in public.