Celebrating 50 years of the Unix operating system

Without the pioneering work of Ken Thompson and his colleages the world would be a very different place

Towards the end of the 1960s, a small group of programmers were embarking upon a project which would transform the face of computing forever. Their goal was to write a multi-tasking, multi-user operating system (OS) and in August 1969, a programmer at AT&T Bell Laboratories started work on the first ever version of Unix.

This programmer was none other than Ken Thompson, and over the course of the next few years, with the support of his colleagues Dennis Ritchie, Brian Kernighan and several others, he developed both the Unix OS and the C programming language. As the former reaches its 50th anniversary, I wanted to take a look at how it has had such a profound impact on the world we live in today.

The building blocks

A lot of the foundation of the Unix OS came from Multics, its predecessor. But the fact that it was written in C is what made this OS so different. At the time systems were rarely portable due to the nature of their design and low-level source language, which meant they were tied to the hardware platform on which they had been authored. But as Unix was written in C, it could be run on myriad different hardware architectures.

But the real value of Unix is its foundation on principals of simple and modular architecture, emphasising the importance of building minimal, concise, clear, and extensible code that can be easily maintained and repurposed.

This is why Ken Thompson's ‘Unix philosophy' soon became a renowned model of modular software design, a lot of which is still applicable today - for instance in the roots of the current cloud function-as-a-service (FaaS) and serverless computing models. In addition, as it was so portable, it was rapidly adopted by those in research and academia, as well as for commercial purposes.

Cloud & Infrastructure Live 2019 returns to London on 19th September 2019. Learn about the latest technologies in cloud, how to keep one step ahead of the regulators, and network with an audience of IT leaders and senior IT pros. The event will include keynotes, panel discussions, case studies, and strategic and technical streams. Best of all, the event is FREE to qualifying attendees. Secure your place now.

The impact of Unix today

Over the past 50 years, the Unix OS has played a pivotal role in the evolution of computing and design. It has inspired some important variations such as Linux, and is so embedded in our day-to-day infrastructure that it's hard to imagine where we would be without it.

Unix is an enabler of technologies such as cloud computing, security systems, virtualisation and mobility. It has been adopted by Global 100 and Fortune 100 companies across a range of sectors including manufacturing, government, healthcare and financial services.

Standards as key to development

Today, the Unix platform is the embodiment of openness. In the beginning, however, the Unix OS was not standardised. Initially, the source code was only licensable via contracts with its owner. In 1975, the first software license on record was sold to the University of Illinois.

However, as a result of the growing number of use cases within academia, in 1977 computer scientists at the University of California, Berkley created the Berkeley Software Distribution (BSD). This, along with developments from AT&T, led to an upsurge in commercial offerings - a time now known as the ‘Unix wars'. During this period, there was a significant drive for standardisation across the community.

Efforts to standardise Unix were boosted by the creation by the Institute of Electrical and Electronics Engineers (IEEE) of POSIX standards to unify the various Unix forks. The Unix trademark was then handed over to The Open Group, a vendor- and technology-neutral industry consortium. This allowed the name Unix to be applied to certified OSs that complied with the Single Unix Specification, a set of standards developed by The Open Group and IEEE.

By collaborating closely with the community, The Open Group continues to develop and maintain the Unix standard. This includes allowing the standard documentation to be reused in open source projects, delivering test tools, ensuring that the standard documentation is freely available on the web and creating Unix and POSIX certification programmes.

As an open standard, Unix takes away the need to compete as the core OS level, instead allowing those who use it to focus on more important issues: driving innovation within the ecosystem based on the platform. It gives integrators the ability to choose the foundation they use for solutions, makes portability easier for software developers and means that customers can concentrate solely on solving business problems, rather than being distracted by integration issues.

The Unix OS has had an unprecedented effect on the technology industry. There is no way the original developers could have foreseen the impact that their creation would have on the world. And as today's computing environments become increasingly diverse and connected, Unix will continue to enable innovation both now and in the future.

Andrew Josey is VP, standards and certification at The Open Group