Multiple Instruction and Multiple Data stream (MIMD):

In this categorization, numerous processing elements and multiple control units are ordered as in MISD. However the difference is that now in this organization multiple instruction streams function on multiple data streams. So, for handling multiple processing elements, several instruction streams and multiple control units are organized in such a way that multiple processing elements are controlling multiple data streams from main memory as shown in Figure below. The processors work on their individual data with their individual instructions. Tasks performed by various processors can begin or complete at different times. They aren't lock-stepped as in SIMD computers although run asynchronously. This categorization exactly identifies the parallel computer. Which means in real sense MIMD organisation is said to be a Parallel computer. All multiprocessor organizations fall under this categorization. Illustrations include; Burroughs D825, C.mmp, Cray-2, S1, Cray X-MP, Tandem/16, HEP, Pluribus, IBM 370/168 MP, Univac 1100/80,  IBM 3081/3084, C.m*, BBN Butterfly, Meiko Computing Surface (CS-1), FPS T/40000, iPSC. 

This kind of computer organisation is represented as:

I_s > 1

D_s > 1

Figure:  MIMD Organisation

Of the categorizations mentioned above, MIMD classification is the largely popular for a Parallel computer. In the actual intellect parallel computers implement the instructions in MIMD mode.