What is a SIM Card & What does it do??

[Shirl51]

I'm a newbie here for sure.... I'm learning alot BEFORE we buy.

I keep reading about the SIM card. What does the SIM Card do?? Do you have to have one? Is it for any particular phone??

We are "shopping" for a cell phone plan...and will probably go with Cingular. There is alot more info out there than I expected!!

Any recommendations is definitely appreciated!!

Thanks,
Shirl

[darkninja]

The sim card is like the brain of your phone. It is what the phone number is actually stored on and connected to. It can also hold phone numbers. All this helps to change phones because you swap your sim card from one phone to another and it is ready to go. That is if the phone you are using is either from your carrier or unlocked. Unlocked meaning any sim card can be used in it. Hope this helps a little

[blkballoon925]

TDMA, for example - used the phones EIN (Electronic Information Number), and IIRC, CDMA (Sprint/Nextel) does the same.

Small correction, this is an ESN - Electronic Serial Number.
http://www.google.com/search?hl=en&l...n&q=define:ESN

[DRC72]

SIM is short for Subscriber Identity Module, a "smart" card securely storing subscriber-related data, such as phone numbers, service details, and memory for storing messages; also called SIM card.

GSM technology uses a SIM to authenticate the phone on the network. So yes, you must have one to be with Cingular (which is only GSM now.)

^^^
Pretty much in a nutshell.

[Isriam]

SIM your social security card. You can change wallets, but you always take your SSN card with you :P

[Jhumien]

SIM your social security card. You can change wallets, but you always take your SSN card with you :P

actually, you arent supposed to carry your ss card with you

[Tstright]

actually, you arent supposed to carry your ss card with you

Why's That?

[DRC72]

Why's That?

If you lose your wallet somebody can gain access to your SS number and identity theft can possibly happen.

[Shirl51]

THANK YOU SO MUCH!! You made it VERY easy to understand!! I'm learnin' this stuff.... My goodness, it's alot to grasp!!

Thanks to all of you......
Shirl

[Tstright]

If you lose your wallet somebody can gain access to your SS number and identity theft can possibly happen.

5 mins with a DL's and that can happen

[DRC72]

5 mins with a DL's and that can happen

I honestly wouldn't doubt it.

[NWSternGirl]

Thanks for asking those questions, Shirl! I have been searching for answers to those questions, myself, before posting the questions. I am shopping for a new phone and will be sticking with AT&T...now Cingular. All I really care about is excellent reception.

I have the Nokia 8260, which uses TDMA. I'm thinking there's not going to be a way to transfer my "phone book" from my old phone to my new one...oy!

[duffwant]

I have a question about upgrading hardware from a non-SIM card phone to a new GSM phone.

My dad is with Cingular and has an ancient Nokia 5160 (or some variation thereof). The battery is dying and he wants to change phones.

Whenever he calls Cingular CS, they tell him to change his plan in order to upgrade. However, he likes his plan and doesn't want to change.

What are his options? Can he buy a PAYG phone and request to change service to it?

Thanks in advance...

P.S. Although he lives in California, I live in Canada, so I don't know all the specifics about hardware updates in the States.

[NWSternGirl]

How about just buying a new battery for it? There are reputable sellers on eBay who sell great knock-offs for a few dollars.

Also, I talked to someone in a local Cingular store who told me that they have a machine that'll transfer the phone book in my ancient phone to the new one...woohoo!

[annapink15]

Thanks for asking those questions, Shirl! I have been searching for answers to those questions, myself, before posting the questions. I am shopping for a new phone and will be sticking with AT&T...now Cingular. All I really care about is excellent reception.

I have the Nokia 8260, which uses TDMA. I'm thinking there's not going to be a way to transfer my "phone book" from my old phone to my new one...oy!

Because you have tdma you wont be able to stay with At&t you'll have to got o the orange side and sign up with cingular. gl