What+is+a+cell+phone+and+how+do+they+work?+-+R

By: Nick D 2012
 * // What C //****// ellpho //****// nes are and How they Work? //**

A cellphone is a device that is used to call or text people, you can also send emails from a phone but it is slower than texting. By 1993 there were 15 million cell phones in use. The technology spread around the world and by the year 2000 there 500 million phones in use around the world. Pretty much everyone was “glued to their phones”. Also in 1993 Larry King (television and radio host) announced on live TV that the cellphones were giving people cancer. Dr. George Carlo (scientist who found out that cellphones gave you cancer) used $25 million on the research on the question that everybody was asking, do cell phones give you cancer. He found out it does and the cellphone companies treated him like an enemy after that. ** Calling and Frequencies **

When you call somebody and end the call and call somebody else the phone frequency changes so you can call that other person. There are hundreds of frequencies that are given in a certain location. Phones are basically little radio signals that you can send and receive. If you are playing on your cell phone in the car and you see a cell phone tower about every 7 to 10 miles you have a good signal and as you get further away you get close to losing the signal there will be another cell phone tower that picks up the frequency of your phone.

** Texting and IM **

You can also email and text from a phone. People text on their phones because maybe they are doing something and don’t really have the time to call so they just text.They made “the first text” on December 3, 1992 and it said “Merry Christmas”. It is estimated that there are 3.6 billion users of text messaging worldwide. There were 6.1 IM is like texting but it is on a computer. It is called instant messaging because it sends a message instantly instead of texting it takes a while to get to the other person. Figure 3 how Texting works and connects with other phone. Figure 2 how instant messaging works and how it connects with other computers.

Glossary:
 * __Cellphones__ are a device that you can use to contact people. You can text them witch is to send a message from your __cellphone__ their __cellphone__ and you can also email on your phone it is also like texting but a little slower.
 * __Instant messaging__ means you can go on your computer and send messages to the person on the other end of your conversation.
 * __Frequencies__ are what the phone uses to connect to the cell towers. If the cell towers __frequency__ was 38 the phone would switch from the __frequency__ it was on to 38.

. Figure 1 this diagram shows how the phones frequency connects with the tower and how if you move closer to the other tower the phone would switch frequencies.


 * Citations: **

Brain, Marshall, Jeff Tyson and Julia Layton. "How Cell Phones Work" 14 November 2000. HowStuffWorks.com

Clive Gifford and Mike Goldsmith London ; New York : DK, 2011

George Carlo and Martin Schram New York : Carroll & Graf Publishers, Inc., 2001.

"telephone." Compton's by Britannica. Encyclopædia Britannica Online School Edition. Encyclopædia Britannica, Inc., 2012. Web. 24 Sept. 2012.