GSM stands for “Global System for Mobile Communications” and is an international standard for 2G cellular networks. In the USA, AT&T and T-Mobile built their networks on the GSM standard.
Central to the GSM standard is the SIM card, making it relatively easy to move service from one device to another. GSM phones are often able to roam onto other GSM networks around the world.
Going forward, legacy GSM networks are being replaced by LTE.« Back to Glossary Index