Applied science extrapolates the principles of science to create new things. Because it has to create something tangible and lasting, only the most solid science will work as a foundation. Theoretical science, which is not easy to apply and extrapolate, may not be real or may not reflect reality. It may only work in the imagination.

For example, when sending men to the moon in the 1960's, they did calculations based on the math behind gravity. Although the math for gravity was accepted as true, nobody was 100% sure it would extrapolate 100% for the expensive and risky human endeavor. Ot was not until after it was applied that it became understood as reality.

Applied science is also the basis for all experiments. In experiments we set up a tangible reality scenario to see if the theory can satisfy the needs of physical reality. This, alone, is not always enough too satisfy the needs of reality. One example of falling short are experiments called magic tricks. One will set up an applied experiment; theory of anti-gravity levitation, using principles of science and engineering, to create an on stage experimental affect that appears to satisfy the needs of reality. This can be misleading.

The real test is not just an experiment based on a clever design, but an extrapolation of the experiment in terms of scale and complexity, so science magic tricks can be filtered out. The engineer is at the interface of reality since he/she is the one who needs to cherry pick science and demonstrate what is real.