These computer print-outs by Manuel Barbadillo would have served as trial pieces, or research, for a later work that would have been produced by hand, such as the two screenprints in the V&A's collection (for example, see E.99-2008). Barbadillo wrote a computer program that enabled him to rotate the U- shaped forms within a grid, to produce a large number of different formations. The set of figures in the top left corner of each design, labelled 'Cuadro Numero' (meaning 'Picture Number'), demonstrates how Barbadillo altered the numerical values in the computer program to explore the relationship of one U-shaped motif to another. Barbadillo would then compare the different outcomes in a larger sequence to decide which image was the most successful, and should be developed further. By using the computer as a tool, Barbadillo was able to process much larger quantities of information than would otherwise have been possible.

These works were produced using a line printer, which was an early form of impact printer. Like a type writer, impact printers use force to literally stamp the ink onto the paper. Print-outs were restricted to black and white, and darker areas or shading, could only be achieved by overwriting one character on top of another.