Because what you don't see in this file is any code a that actually says put a letter of the alphabet at the top left hand corner of the screen and then put the next character to the right in other words, I'm taking for granted at this moment in time that my computer knows how to print something to the screen.

就是这些你在本文件中看不到的一些代码,实现了将首字母,放在屏幕的左上角,然后把其他字母加在其右边，我想当然地认为,我的电脑知道如何打印相应信息到屏幕上。

哈佛公开课 - 计算机科学课程节选