Bluetooth - A small very low power transmitter/receiver that allows a mobile to connect to nearby devices such as ear pieces and car loudspeakers.
EDGE (also known as Enhanced GPRS or EGPRS) is a data system used on top of GSM networks. It provides nearly three times faster speeds than the outdated GPRS system. The theoretical maximum speed is 473 kbps for 8 timeslots but it is typically limited to 135 kbps in order to conserve spectrum resources. Both phone and network must support EDGE, otherwise the phone will revert automatically to GPRS.
Prepaid involves paying upfront for a service and receiving or using that service afterwards. Purchasing a prepaid card for cell phones tops up credit onto a cell phone. This credit can then be used for phone calls, text messages, and other services.