translation.en: And I finally got what's been going on. This is Kernigan and Ritchie inventing UNIX on a PDP. PDPs came between mainframes and minicomputers.
translation.zh: 后来我也搞清楚了到底会发生什么。 Kernigan 和 Ritchie 在一台PDP机器上发明了UNIX操作系统 PDP是介乎大型机与微型机之间的一种机器