If you feel exposed without a text book, you really have to have a textbook, John actually I'm going to reuse that word, John, at least suggest it, on the course website.

如果你觉得没有教科书就缺乏安全感的话，那你真的需要一个了，其实我应该重新使用这个词儿，至少是建议，你能在课程网站上找到。

麻省理工公开课 - 计算机科学及编程导论课程节选