This document discusses column chromatography, which uses a stationary phase in a column to separate mixtures based on differences in how components partition between the stationary and mobile phases. Column chromatography can be classified as adsorption or partition chromatography depending on whether the stationary phase is a solid or liquid. Key aspects covered include choosing an appropriate stationary phase based on the components to be separated, packing the column, introducing the sample, developing the column using isocratic or gradient elution, detecting and collecting separated components, and factors that influence column efficiency.