This soft­ware nev­er crash­es. It nev­er needs to be re-boot­ed. This soft­ware is bug-free. It is per­fect, as per­fect as human beings have achieved. Con­sid­er these stats : the last three ver­sions of the pro­gram — each 420,000 lines long-had just one error each. The last 11 ver­sions of this soft­ware had a total of 17 errors. Com­mer­cial pro­grams of equiv­a­lent com­plex­i­ty would have 5,000 errors.