Difference between product development and product re-engineering?

Answer 1

Probably a rather philosophical question, but if you want to make a quote it is the difference between an architect and a construction worker. Engineers design a framework and decide how the building works in its entirety and how it interconnects with the outside world and programmers execute the master plan, putting up the walls and installing the Plumbing and electricity.

Answer 2

"Forward" engineering is the process of constructing a system for a specific purpose. Reverse engineering is the process of deconstructing a system in order to learn how it works and how to make it do things it wasn't designed to do.

Answer 3

Engineering: making new stuff

Re-engineering: making old stuff better