Simultaneous multithreading
The Intel Pentium 4 was the first modern desktop processor to implement simultaneous multithreading, starting from the 3.06GHz model released in 2002, and since introduced into a number of their processors. Intel calls the functionality Hyper-Threading Technology (HTT), and provides a basic two-thread SMT engine. Intel claims up to a 30% speed improvement compared against an otherwise identical, non-SMT Pentium 4.