harmonics from non-linear loads

[makeitwork]

Hi all,
Assuming a sinosoidal AC supply to a non-linear load which draws distorted current. My question is
1. how does people define non-linear load in general,is it purely resistive or it contains reactive components?

2.Assuming the distorted current waveform is in phase with the voltage,the displacement factor=1 and distortion factor equals to less than 1,which gives a Total power factor of less than 1 and therefore draws reactive power right? Can we conclude that harmonics draws reactive power? or does it draw active power as well?

3.how do we calculate the active and reactive power drawn by these harmonics?

Thanks

Regards,