OS: Linux

The origins of Linux

Linux borrowed many ideas and solutions from Unix. Both OSs follow the set of standards called POSIX (Portable Operating System Interface). POSIX defines the interfaces between applications and the operating system. The use of the same standards for Linux and Unix led to similarities in their behavior, so let’s go over the history of Unix first.

Multics

The Unix OS appeared in the late 1960s. It was created by two engineers, Ken Thompson and Dennis Ritchie, from the Bell Labs company. Before Unix, however, they developed the Multics OS. This was a joint project of the Massachusetts Institute of Technology (MIT), General Electric (GE), and Bell Labs. Multics was planned as an OS for the new mainframe GE-645, shown in the figure below, by GE.

The developers applied several innovative solutions to Multics. One of them was time-sharing. The GE-645 mainframe was the first commercial computer where several users could work simultaneously and share their resources.

However, Multics turned out to be too complicated. The project consumed more time and money than it was expected to, so Bell Labs decided to discontinue it. However, the project was interesting from a technical point of view, and many Bell Labs engineers wanted to continue working on it. Ken Thompson was one of them.

Thompson decided to create his own operating system for the GE-645 computer. He started to write the system kernel and duplicate some Multics mechanisms. However, General Electric soon demanded the return of its GE-645. Since Bell Labs had only received the computer on loan, Thompson lost the hardware platform for his development.

Space Travel and PDP-7

While he worked on a Multics analog, Thompson also had a pet project: to create a computer game called Space Travel. He launched the game on the past-generation GE-635 computer. It had the GECOS90 OS. GE-635 consisted of several modules, where each module was a cabinet with electronics. The overall ...