An I Ching interpretation is performed by making six binary decisions (a hexagram). This is called 'casting the I Ching'. These are written down as a stack of six solid or broken lines. This was traditionally done either by tossing yarrow stalks or coins, although there is no reason why the hexagrams can't be generated by some other means (such as a computer program).
There are actually four possible values for each of the lines; the two on/off values, and a line which changes from on to off or vice versa. Thus one cast of the I Ching can generate several different hexagrams, which adds depth to the interpretation. The sophistication of this method has not escaped modern interpretation, and the four-valued logic has been compared to the biochemistry of DNA amino acids. How a Neolithic shamans' divination technique presaged the basic logic of the human genome is one of the ageless mysteries.