OT: The SIM card!
When my father-in-law upgraded his handset last Summer the dealer in Sweden basically said the old handset was worthless (could be sold as a paperweight in a pinch). He did remove a small, cardboard-like chip from behind the battery which apparently had either his subscriber ID information or a couple KB of memory used for storing numbers and names.
Aus, this is the SIM card (Subscriber Information Module)which is an essential part of the GSM cellular system. Essentially, it contains your phone number, as well as letting you store other info such as often-used phone numbers on it. So, you can for example, take the SIM out of your phone, put it in another, make calls and receive calls on that phone, and all the bills will go to you, as well as the calls, rather than the owner of the phone.
I wouldnt say the SIm card is cardboard like, its much more akin to MMC, looks the same but smaller, its about the same size as the chip in a smart card. if you've seen one of those. say 1/2 inch by 1/3 inch. Also comes in a larger package which is credit card sized but the chip is still the same size. The chip is not just memory, it also does processing, and contains encryption routines for example.
When I got a new phone at work recently I just put the SIM card from my earlier phone in it, and I was up and running.
Joe |
