Definition of "EV-DO" Commonly known simply as EV-DO, CDMA 1xEV-DO is a 3G technology add-on for CDMA networks that allows for theoretical download speeds as fast as 2.4576Mbps, though actual rates tend to be far slower. Originally known as CDMA Evolution Data Only, EV-DO is today generally regarded as standing for Evolution Data Optimized for what are likely marketing purposes. 1xEV-DV (Evolution Data Voice) is the technology that was originally destined to handle the future 3G voice and data needs of CDMA networks, but has failed to catch on in North America. Instead, 1xEV-DO Rev A has been developed, which allows for faster uplink speeds than the original EV-DO spec, which relies on the older, and much slower, 1xRTT system for uplink connections.

Definition of "2.5G" 2.5G is a sometimes used term that refers to GPRS class wireless data connectivity. It is not a formal standard.

Definition of "3G" 3G, or Third Generation, is a somewhat generic term for network technologies that the ITU classifies as part of their IMT-2000 specification. Generally, wireless network technologies must be able to provide a mobile device with a downlink connection speed of 384kbps in order to be considered a 3G technology. The most used 3G technologies are WCDMA, CDMA 1xEV-DO, and, technically, EDGE and CDMA 1xRTT.

Definition of "3GPP" The 3GPP is a standards body that works within the scope of the ITU to develop 3rd (and future) generation wireless technologies that build upon the base provided by GSM. The group is responsible for the UMTS standard, as well as HSDPA, HSUPA, HSPA+, and LTE.

Definition of "4G" 4G is the term used to refer to the next wave of as yet unknown mobile technologies that will be used to replace current 3G networks. It is expected that WiMAX will be one of the favored 4G technologies.