And the telephone companies in the United State, generally about 200 billion dollars a year carrying long distance telephone conversations and they thought this conversations might be carried for free over the internet was quite shocking to them. Of course free is very low price, and they are not like it to be free.

美国的各电话公司，一般大约有每年2千亿美元,来自长途电话会话，他们认为,这些会话有可能通过互联网免费传输,对他们来说是相当震惊的，当然了,免费是很低的价格了，他们不希望它免费。

麻省理工公开课 - 媒体、教育、市场课程节选

It's a little more involved on a PC but it's all free, the software you can download, and Linux in similar operating systems generally come with a compiler or you run a simple command to get it.

在PC机上有点复杂，但是它是免费的，你一般下载的软件，类似Linux的操作系统等等通常都需要,一个编译器，或者你可以运行一些简单的指令来获取。

哈佛公开课 - 计算机科学课程节选