ABSTRACT.

As foundation of polynomial approximation, uniform convergence is replaced with basic nonstandard notions like S-continuity and standard part.

In the real case, Weierstrass' approximation theorem is generalized to G-delta sets.

In the complex case the standard compactness requitements also disappear.

Standard applications include a direct proof of a generalized Bernstein theorem on analyiticity of infinitely smooth and of continuous functions.