But thankfully now in 2010, we're at the point where there's a whole lot of free and open source software that you can integrate into your projects that other nice people have made available.

不过幸好在2010年,现在有很多可用的开源,代码软件，你可以将其融合,到你的工程中。

哈佛公开课 - 计算机科学课程节选

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