Answer: See section 1.2.1 to 1.3.3 for what a microprocessor is. Section 1.4 indicates what a microcontroller is. Essentially, a microcontroller is obtained by integrating the key components of microprocessor,RAM, ROM, and Digital I/O onto the same chip die. Modern microcontrollers also contain a wealth of other modules such as Serial I/O, Timers, and Analogue to Digital Converters. There are a large number of specialised devices with additional modules for specific needs. eg. CAN controllers, Serial Peripheral drivers.