(Commonly abbreviated to "386", trademark "Intel386") The successor to the Intel 80286 microprocessor. It was the first Intel processor with 32-bit data and address busses. It can address four gigabytes (2^32 bytes) of memory; however, 16 megabytes is a typical maximum in IBM PCs. The 386 allows multiple application programs to run at the same time (when running under 386-specific operating systems) using "protected mode". The first IBM compatible to use the 386 was the Compaq 386, before IBM used it in high-end models of their PS/2 series. It is also used in HP's RS series and many others. It does not require special EMS memory boards to expand MS-DOS memory limits. With the 386, the EMS standard can be simulated in normal extended memory, and many DOS add-ons provide this "Expanded Memory Manager" feature. See also Intel 80386SX, BSD386.