OFDM is widely used in emerging technologies such as LTE, 4G, and 5G. Basically, OFDM (orthogonal Frequency Division Multiplexing) is a modulation scheme that enables high bandwidths.
As of now, it is the most efficient modulation scheme that has been made available.
Check out the following articles:
http://rfmw.em.keysight.com/wireless/helpfiles/89600B/webhelp/subsystems/wlan-ofdm/Content/ofdm_basicprinciplesoverview.htm
http://mobiledevdesign.com/learning-resources/orthogonal-frequency-division-multiplexing-ofdm-faq-tutorial