difference between microprocessor and microcontroller

many of us work with microprocessors and microcontrollers..or have heard about them but many of them dont know the difference between them.
by microprocessor is meant the general purpose microprocessors such as intel's x86.these microprocessors contain no RAM,no ROM,and no I/O ports on the chip itself.for this reason they are known as general purpose microprocessors.that is as a system designer when we use these general porpose microprocessors we should add RAM,ROM,I/O ports and timers externally.
but this is not the case with the microcontrollers.a microcontroller contains a CPU(or microprocessor) in addition to a RAM,ROM,I/O ports and a timer all on a single chip,that is all embedded together in a single chip.