What does GSM mean? Are all cell phones GSM?

Answer 1

GSM stands for Global System for Mobile communications...although it's original offical name is Groupe Spécial Mobile.

it was developed and first used in Europe and has become the standard for cell phone communication. it slowly worked it's way into the US in the form of Sprint's first PCS network, which changed later to CDMA. Voicestream (later TMobile) was the first full-time operator of a GSM network, followed by AT&T which became Cingular in the merger.

GSM is a standard comminucation system for cell phones..it basically means that all GSM phones can talk to all GSM networks regardless of what provider it is..and it also calls for interoperatbility between GSM networks.

not all phones are GSM phones. the only GSM networks that exist currently in the us are Tmobile, Alltell and Cingular. Nextel's iDen network uses a modified GSM system.that's not compatible with GSM networks.

phones put out by Verizon and Sprint use a different network system entirely.

Answer 2

First lets talk about a locked phone. A locked phone means that only the SIM from the carrier that the phone is locked to will work. So if you have an AT&T phone only an AT&T SIM will work. An unlocked phone allows any SIM from any phone company to work. Phones with SIM cards only work on the GSM cellular network. In the USA, that would be AT&T and T-mobile. Verizon and Sprint use CDMA and are incompatible with GSM phones. Having said that, there is ONE BIG WARNING that I have to give you about unlocked GSM phones. There are multiple frequency bands that are used for GSM phones. The two that are used internationally are different from the two that are used in the USA. Thus you have to ensure that the frequency bands for the unlocked phone you are looking at have the frequency bands for use in the USA. For CDMA carriers Verizon and Sprint, I believe the official word is that they will only activate phones that were originally on their network. Thus a Verizon phone cannot be used on Sprint or vice versa. Others have claimed that it can be done. I don't have any experience in that aspect so I cannot say what is right.

Answer 3

Global Systems for Mobiles. Not all phones are GSM. There's different technologies available from different carriers. TDMA, CDMA, UMTS, EDVO, IDEN, wideband CDMA. Lots to choose from.