What is the difference between ion exchange chromatography and affinity chromatography?

The difference between these two chromatography methods is derived from their different working principles. Ion-exchange chromatography is used to separate charged analytes, which is based on the electronic interaction between the column and the target molecule who has an opposite charge to that of the stationary phase surface. However, for affinity chromatography, it proceeds because target molecules, whether charged or not, have a high affinity for the stationary phase due to some specific interactions such as antigen-antibody interactions and enzyme-substrate interactions.