[quote name='Rags']I may be dense, and I probably am on cell phones but I have a question. Could I get this phone and use a pre-paid card? I see people saying I would have to get it "Unlocked" and "sim-card" but I have no clue what a simcard is. Sorry if it's a stupid question, I don't know much of anythin about cell phones. I've been wanting a prepaid phone, but the phones themselves on those prepaid deals are usuallly like $120.[/QUOTE]
The SIM card is the small chip that you insert into your phone, usually under the battery. It holds the account information and is required to use the phone. Not all types of service use a SIM. All GSM phones (AT&T/Cingular & T-Mobile) do, as does iDEN (Nextel/Sprint) though the two are not interchangable. I believe PCS does as well. CDMA and TDMA (the older American digital cellular standards) do not use SIM cards.
There are three things to consider when looking at the interoperability of a phone. One, the type of network. Some are interoperable, but for our purposes GSM only works on GSM. This means your push to talk iDEN Nextel won't work with your T-Mobile service no matter what you do. Second is the frequency. Only iDEN and GSM are international, and iDEN uses a standard freuquency. A dual band phone generally only works in the US and parts of Asia. A tri-band phone will work anywhere in the world. Finally, if the phone is locked. Providers will usually lock a phone in the phone's firmware so that despite whatever technical capacity the phone will only work with their SIM cards. This means that you can't use a Cingular branded phone with your T-Mobile service unless it's been unlocked.
So, to sum up the answer to your question, you will be able to use this phone out of the box with Cingular service. If you unlock it (should be easy for a Nokia) you can use it on any GSM network in the US (it's only dual band) with the prepaid or month to month SIM card of any GSM provider.