Apple Computer and Tenon Intersystems took two different approaches in putting Unix on the Macintosh. After about a minute, a login screen appears, and the system has become a Unix workstation. To go back to MacOS requires a complete reboot. When logging in, you choose either the familiar Mac Finder, an X11 window manager, or a tty-like console. The window that comes up when you click on a Unix command is brought to you by a slick program called Commando.
Commando is an instant refresher course in each command's options.
Type cpio in a Command Shell and press Command-K, and up pops instant help. A very helpful addition to Unix for Mac users. An alternative interface is standard X11, which is fully supported, as is Apple's MacX product. Plus, you can run most Macintosh applications, except for those which require direct hardware control. To start MachTen, you click on the MachTen icon, and it launches Unix as an application.