RAM You probably know your computer has something called RAM which is where documents and programs live just temporarily while you're running them 'cause RAM tends to be pretty fast and whereas your hard disk is where programs and files live permanently.

也许你知道电脑有一个,正在使用的程序和文件都暂时存放在那里,而且会加快电脑速度,而硬盘是程序和文件,永久存储的地方。

哈佛公开课 - 计算机科学课程节选

When you're working on a file, it's saving constantly to RAM but also hopefully to disc, the hard disk so you don't actually lose it if the power goes off.

当你打开一个文件，它不断地保存在内存中,但对于光盘，硬盘,当你断开电源的时候，数据不会丢失。

哈佛公开课 - 计算机科学课程节选

Because you can come up with an infinite number of values but if you have a finite amount of space and certainly a computer has a finite amount of disk space or RAM, you have to make approximations.

你可能会碰到一些无限的值,如果你只有有限的空间,废话，电脑当然只有一个有限的磁盘空间,或RAM，我们得做一些近似处理。

哈佛公开课 - 计算机科学课程节选