Zap means to remove or obliterate. In zapping a portion of a spectrum, one replaces it by a straight line segment. The information content as well as the noise content of that portion of the spectrum is then lost. Zapping has many applications in the manipulation of spectra and therefore a versatile, interactive Zap program has been created as part of the GRAMS software. Three uses of Zap within QASoft are: (1) creating a noise-free zero absorbance spectrum to carry integration parameters, (2) removing unwanted CO lines from single-beam background spectra of nitrogen, and (3) removing unwanted water lines and noise from the CO2 subtraction spectrum.