The three key areas of difference between microprocessors and microcontrollers are hardware structure, application area, and instruction set characteristics.

A microcontroller might contain an embedded processor as part of its makeup, but also combines other computer parts, such as memory and signal registers, in a single chip.

It comes as no surprise that differences exist among these layered PCB types. This article is devoted specifically to understanding the differences between 2- and 4-layer PCBs.