In Fred Brook's Mythical Man Month chapter 4 (Aristocracy, Democracy, and System Design) page 49, he says:
As Blaauw points out, the total creative effort involves three distinct phase: architecture, implementation, and realization ...
implementer has plenty to do ... designing module boundaries, table structures, pass or phase breakdowns, algorithms, and all kinds of tools
...Meanwhile, on the realization level there is much to be done also. Programming has a technology, too. If the machine is a new one, much work must be done on subroutine convention, supervisory techniques, searching and sorting algorithm.
What is the difference between implementation and realization?
To me, an architecture is more related to specification descriptions or diagrams, whereas implementation is more to programming/coding, and it seems like the same as realization.