We propose an interpretation of nonrelativistic quantum theory which can be considered a generalized Copenhagen intepretation. The uncertainties (i.e., DELTA-q and DELTA-p) in Heisenberg's uncertainty relation DELTA-q . DELTA-p greater-than-or-equal-to h/2 can be characterized as (average) errors in an approximate simultaneous measurement if the interpretation proposed here is accepted in nonrelativistic quantum mechanics. Under this interpretation, the (discrete) trajectory of a particle (like "Wilson chamber") is significant enough. We propose to analyze this trajectory numerically.