HSDPA (High-Speed Downlink Packet Access) is a 3G (third generation) protocol to allow mobile phones to have higher data transfer speeds and capacity for use on things like mobile broadband.

At present speeds of 1.8, 3.6, 7.2 and 14.4Mb are available but as the technology evolves then faster speeds are likely to become available, much like how fixed line broadband evolved to be able to offer faster speeds.