Nokia Digital Cell PhoneMillions of people in the United States and around the world use cell phones. They're great gadgets: with a cell phone, you can talk to anyone on the planet, wherever you are! These days, cell phones offer an incredible range of features, and new ones are being added at a breakneck pace. Depending on the cell phone model, you can: Store contact information Create to-do or task lists Keep track of appointments and set reminders Use the built-in calculator for simple calculations Send or receive emails Get information (news, entertainment, stock prices) from the Internet Play simple games Integrate other devices such as PDAs, MP3 players and GPS receivers But have you ever wondered how a cell phone works? What makes it different from a regular phone? What do all these confusing terms like PCS, GSM, CDMA and TDMA mean? In this article, we will discuss the technology behind cell phones so you can see how amazing they truly are. If you're considering purchasing a cell phone, be sure to check out How Buying a Cell Phone Works to learn about everything you should know before making a purchase. Let's start with the basics: In essence, a cell phone is a radio. One of the coolest things about a cell phone is that it's actually a radio - an extremely sophisticated radio, but a radio nonetheless. The telephone was invented by Alexander Graham Bell in 1876, and wireless communication originated with Nikolai Tesla's invention of the radio in the 1880s (formally introduced in 1894 by a young Italian named Guglielmo Marconi). It was only natural that these two great technologies would end up being combined! In the dark days before cell phones, people who really needed mobile communications capabilities installed radio phones in their cars. In the radiotelephone system, there was one central antenna tower per city, and perhaps 25 channels available on that tower. This central antenna meant that your car phone needed a powerful transmitter, large enough to transmit over a distance of 40 or 50 miles (about 70 km). It also meant that few people could use the radiotelephones -- there simply weren't enough channels. The genius of the cellular system lies in dividing a city into small cells. This allows for widespread reuse of frequencies within a city, so that millions of people can use their cell phones simultaneously..