The word chromatography comes from two Greek words meaning "color" and "to write". Chromatography is one of the most important analytical techniques used by chemists. Several forms of chromatography have been developed that can be used to separate many kinds of mixtures, not just those containing colored components. All chromatographic methods separate the components of mixtures by distributing the components between stationary and mobile phases.

You can use a simple chromatographic technique, paper chromatography, to find out if ordinary black marking pens contain only black ink, or a mixture of colored dyes.