In the old days , a designer working on an airplane wing handed a bunch of punch cards to the computer operator and waited a week to get back thousands of numbers on fanfold paper .

那时候，一个设计飞机机翼的工程师会把一大堆穿孔卡片交给电脑操作员，等上一个星期才能拿回来成千上万的数字，而且是写在复写纸上的。