Difference in Motorola 64 k and x86 processors?

What is the difference in Motorola 64 k and x86 processors?

The instructions are very similar however the difference in architecture evident. 68K processors have 16 23bit general purpose registers named from A0-A7 and D0-D7. A0-A7 can hold addresses in indirect memory accesses. These can also be used as software stack pointers. Stack in 68K is not as rigit a structure as it is in x86.