This plotter drawing was created using a computer program written by the artist. A plotter is a mechanical arm that holds a pen or brush and is linked to a computer that controls its movements. Plotters were one of the few available output devices for computers in the late 1960s. Mohr began using computers in his art in 1968, and this is one of his earliest plotter drawings. The 'P-18' of the title refers to the particular computer program used to generate this drawing. From one program Mohr could produce a series of drawings. The V&A holds two other drawing that were also created from this same program (see V&A museum numbers E.96-2008 and E.115-2008).

In 1969, access to computers was difficult owing to their size and cost. Mohr applied to the Paris Institut Météorologique for permission to use their computer and plotter. It is likely that he created this drawing whilst at the Institute.

Mohr began life as an expressionist painter and jazz musician but in the 1960s began exploring geometric forms and moved towards a more objective, systematic way of working that anticipated his use of the computer. Mohr underpins his computer programs, or algorithms, with precise mathematical logic. The computer enables Mohr to create very complex algorithms which would otherwise be too difficult and time consuming for humans to process.