Right, and just to get a sense of this, let's look at a simple little example, so on your hand-out, you'll see I've got a little piece of code that says assuming I've got one of these points, I want to do things with it, for example I might want to add them together.

这些数组中的一个，你怎么能够知道，它是哪种类型的呢？,你怎么知道它是以笛卡尔坐标,表示的还是以极坐标,形式表示的呢？,你没有可以用来区分的东西，你没有说明这种信息,聚集实际上的意义。

麻省理工公开课 - 计算机科学及编程导论课程节选

They're used by the body for pretty immediate energy where fat is a little bit more long-term energy, and there are many types of sugars-- and these are things that you've heard-- glucose and sucrose being the most common things that you can consume in ordinary foods, and then lactose of course, from milk.

碳水化合物被身体当做是直接能源,而脂肪则更像是一种长期能量,糖的种类有很多,这些类型你们已经听说过,葡萄糖和蔗糖是最常见的形态,你们可以在一般的食物中获取,乳糖,显然来自于乳类

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

And I don't quite remember from reading or from class how big these things are, well, it turns out -- and this is sometimes useful, later on more likely than now -- but C has a size of operator that takes an argument in parenthesis and it will tell you how much space is used to store that particular data type.

我不太记得类中的这些类型,是多大的，嗯，结果是--这个在以后比现在，可能是更有用的--不过C语言中有个sizeof的操作符,其中括号里有一个参数,它会告诉我们，要存储一个类型的数据,需要占用多大空间。

哈佛公开课 - 计算机科学课程节选