Someone-- or someone had to implement, had to write a tool called printf that itself takes input between quotes and produces as output some characters on the screen.

需要有人去实现，这个printf函数,以双引号间的信息为输入,输出相应字母到屏幕上。

哈佛公开课 - 计算机科学课程节选

So you have to somehow convert the source code, the C code into 0s and 1s and for that process there exist this tool called a compiler that someone else wrote that takes this stuff as input and produces this stuff as output.

所以你必须把源代码，即C语言代码转换成二进制文件,这个过程就需要我们提到的编译器了,它是由别人编写的一个软件，以这些代码作为输入,将会产生的输出。

哈佛公开课 - 计算机科学课程节选

And conceptually, the idea of cubing a value feels like you could package that up into a little box, a little tool that takes input, a value, and returns output the answer A* so you don't have to constantly do A star, A*A So this program ,at the end of today, is pretty much the same thing.

概念上，算一个值的立方就像是,你可以把一个值打包放在一个小盒子里,一个用来接收输入的工具,一个值，然后返回一个答案,所以你并不需要一直使用，等等。，A，star，，A，，and，so，forth。,这个程序，最后，是一个差不多的东西。

哈佛公开课 - 计算机科学课程节选