Types of Microprocessors according to there emergence are

Complex Instruction Set Computer (CISC)

Where most of the work is to perform by Microprocessor itself, the philosophy reduced the Line of Codes or instruction and burden processor to perform most of the task. CISC architecture was first used by Digital
Equipment Corporation PDP 11 family of minicomputers.

Reduced Instruction Set Computer (RISC)

Where most of the work is to perform by the software itself, the load on a processor is very low and hence it is called future processors. The RISC architecture was used by Apple Corporation's Macintosh computers, IBM's RISC System/6000 workstations and Sun Microsystems's SPARC.

Very Long Instruction Word (VLIW)

In this architecture a compiler breaks instruction into basic operations to be performed by processor. VLIW is the next step of RISC. In this philosophy complication is moved from the hardware to the software so it reduces the hardware cost.

Superscalar Processors

They are competent of performing more than one instruction in each cycle. In this philosophy concept of cache, parallel processing and floating point were introduced.
Few other are
General Purpose Processor (GPP)
Special Purpose Processor (SPP)
Application-Specific Integrated Circuit (ASIC)
Application-Specific Instruction-set Processor (ASIP)
Digital Signal Processor (DSP)