What is Baseline in Chromatography?

Definition of baseline in chromatography:

The baseline in chromatography is the stable signal level recorded by the detector in the absence of analyte elution. The baseline represents detector response when only the mobile phase passes through the system. A stable baseline indicates that no analyte peaks are present during that portion of the chromatogram. Baseline deviations occur when detector noise, drift, or system disturbances affect the signal.