I know everyone's answered your question, but I wanted to chime in myself. LTE is the network bandwidth that allows cellular costumers to surf at a higher rate of speed. CDMA/GSM are types of broadcast signals used by cellular carriers. Every cellphone in America uses one of these two transmission protocols to transmit wirelessly to the cellular towers.
So as I understand it:
Types of Internet transmissions for Cellular Networks
3G - Third Generation Network. Allowed people to start using their cellphones for video transmission and made networks faster. Usually 1.0 Mbs or a little higher depending on traffic on the network and signal strength.
LTE - Newest Generation of network. Usually marketed as 4G LTE, this is more of a transitional network between 3G and 4G until 4G can be perfected. Speeds are still dependent on signal strength and number of users on the network.
4G - Forth Generation Network. (I've also heard this called LTE Advanced.) Will be capable of providing up to 100Mbs speeds with a strong signal and limited numbers of users. Not available yet, but they are working on it.
Companies that use GSM and CDMA
CDMA - Verizon, Sprint, Metro PCS, and US Cellular
GSM - T-Mobile and AT&T
Sorry for such a long post, but I wanted to get that out there. Hopefully I didn't make too many mistakes.