Differential chromatogram:

A differentiating detector provides a response proportional to the concentration or mass flow rate of the eluted elements. The most familiar instance of a detector responding to concentration is the thermal conductivity detector (TCD). The most familiar example of a detector responding to mass flow rate is flame ionization detector (FED). The chromatogram produced through a differentiating detector consists of a series of peaks, every of that corresponds to a different solute. The area under each peak is proportional to the total mass of that solute. Differentiating detectors are most generally used since off their accuracy and convenience.

Figure:  Differential chromatogram