Operating systems (OS) form the fundamental software layer bridging computer hardware and software applications. They manage resources, provide interfaces, and enable programs to function. OSes have evolved dramatically – from rudimentary batch processing programs to today‘s sophisticated mobile platforms powering billions of devices globally.
This comprehensive guide traces the complete history of operating systems.
What is an Operating System?
An operating system is software managing computer hardware and software resources. It provides services facilitating usage like:
- User interface – Command line or graphical interface for user interaction
- Resource allocation – Memory, storage, input/output device control
- Task scheduling – Determining program execution order
- Multi-tasking – Concurrent execution of applications
- File systems – Organizing data storage across media
- Networking – Communicating with remote systems
- Security – User accounts, permissions, encryption
Without an OS, a computer is unable to leverage resources as needed by software. Early computer systems relied on physical setups like switchboards, patch cables, and configuration settings. Operating systems automate resource sharing through programmatic allocation.
Modern OS examples include Windows, MacOS, iOS, Android and Linux. But operating systems predate even programmable digital computers.
The Genesis of Operating Systems (Pre-1950s)
Operating systems originated not in computers, but electromechanical systems like teleprinters. Early telegraph machines (1850s) relayed signals to print text remotely. Rudimentary "operating systems" handled text queueing and buffering across linked devices.
AT&T‘s 1915 automatic switching system expanded these concepts. Control units acted as an early OS – routing call traffic and managing connectivity. Operating systems slowly grew more advanced with telephone exchange growth over the next few decades.
The Computer Age Dawns (1950s-1960s)
The first commercial digital computers (1951) had no operating system. Machines like the UNIVersal Automatic Computer I (UNIVAC I) ran one job at a time from instructions on metal tape reels or stacks of punch cards. Operators manually loaded programs using switches and cabling.
General Motors (GM) debuted the first true OS in 1956 – the GM-NAA I/O for the IBM 704 mainframe. It handled buffered input/output between the CPU, disk storage and tape drives via a library of software services. Programs interfaced the library to leverage its capabilities.
This system increased reliability and eased 704 operation compared to manipulating hardware directly. But functionality was still limited – the 704 CPU could only run one job at a time.
Batch processing was the next evolution, reaching maturity by the 1960s. Jobs were "batched" rapidly from magnetic tapes – outputting results to printers and tape drives. Operators stacked task queues without manual intervention. The OS scheduled app execution based on priority. Still no multi-tasking, but throughput improved dramatically.
Time-Sharing, Multics and UNIX (1960s-1970s)
Engaging directly with a mainframe via screen and keyboard was costly. DARPA funded "time-sharing" projects (including Multics and UNIX) to increase utilization. Time-sharing lets multiple users run applications concurrently on one computer. This technique relies on complex OS scheduling with rapid context switching.
Multics (Multiplexed Information and Computing Service), begun in 1964, was an influential early time-sharing OS. Multics provided a hierarchical file system, user permissions and sophisticated memory management. Security was a priority given the multi-user nature.
AT&T pulled out of the Multics project in 1969. Ken Thompson, Dennis Ritchie and others continued exploring time-sharing at Bell Labs. Their efforts resulted in UNICS (UNIplexed operating and Computing System) – later shortened to UNIX.
UNIX adopted simpler design goals compared to Multics but shared many concepts. It was written in the C language – unusual for the era – offering great portability. AT&T licensed UNIX widely to academia and corporations in the 1970s and 80s. Versions like SunOS/Solaris, HP-UX and IBM AIX still see usage today. The open source Linux OS builds on UNIX foundations.
Xerox Alto and the Dawn of GUIs (1970s)
While text UIs suffice on servers today, personal computer interaction necessitated more friendly formats. Graphics terminals existed previously (early 1960s), but were exceedingly expensive.
Xerox‘s Palo Alto Research Center (PARC) piloted one of the first personal computer operating systems with a graphical UI (GUI) – the Alto OS in 1973. The Alto featured windows, icons and menus driven by a mouse pointer decades before the design became ubiquitous.
Apple and Microsoft both leveraged PARC‘s Smalltalk GUI innovations later in popular products like the Macintosh and Windows. Interestingly, Apple had full access to PARC‘s concepts under an IP sharing agreement which Xerox later deeply regretted.
The Personal Computer Age (1970s-1980s)
Newly affordable microcomputers in the mid 1970s – like the MITS Altair 8800 (1975) – brought computing to hobbyists and small businesses. These discarded batch processing in favor ofinteractive usage models through terminal programs.
Microcomputers often shipped without built-in OSes, relying on interfaces provided by programming language monitors like CP/M‘s CCP – the Control Command Processor. Demand quickly grew for more advanced, standardized software environments on these machines.
Disk operating systems (DOS) filled this need – providing file management, program loading/relocation, basic I/O routines and utility functions. ASCII Corporation‘s CP/M (1974) was the first microcomputer DOS success story. It dominated business systems until IBM PCs standardized on Microsoft‘s MS-DOS model.
Apple took a huge early lead in OS UI design on personal computers. The Lisa (1983) featured advanced multitasking in its graphical shell. The first Macintosh OS (1984) built on this foundation – adding spatial file management via folders. MS-DOS remained text based in contrast.
Microsoft‘s first attempt at a GUI OS – Windows 1.0 (1985) – faced scathing criticism as unsuitable for professional use. Windows 3.0 (1990) was the first verging on usable – but only found success paired with its office suite. Windows 95‘s release in 1995 finally challenged MacOS‘s UI dominance by copying key visual metaphors.
The Open Source Movement and Linux (1991 Onwards)
Proprietary commercial operating systems reached maturation by the early 1990s. At the same time, Finland student Linus Torvalds began exploring open source OS design – specifically for IBM PC compatibles. This work coalesced into the Linux kernel in 1991.
The Linux kernel had an ad-hoc following among students and hackers for years before seeing serious commercial adoption in the late 1990s. Its model of community development by distributed programmers was unprecedented. Linux provided companies an open platform alternative to UNIX.
Red Hat Enterprise Linux formed in 1994 to service growing Linux demand in business contexts. Telecom/networking vendors began leveraging Linux extensively by the 2000s for cost and security advantages. Google, Amazon and Facebook built massive Internet infrastructures around Linux – shaping perceptions globally.
Open source OSes now see ubiquitous deployment from IBM mainframes, to Android phones, network switches, smart TVs and more. Linux forms the foundation for many embedded and IoT solutions. The collaborative development model pioneered by Linux became integral to modern software.
The Mobile Revolution (2000s Onwards)
Operating systems underwent a paradigm shift in the 2000s driven by smartphones – high capability mobile cellular devices with large touchscreen displays. iOS and Android lead this segment today.
The iPhone launched in 2007 running iPhone OS 1.0 (later renamed iOS). iOS was built on DNA from earlier Apple OSes like classic Mac OS and OS X. Hallmark UI traits like multitouch gestures persisted across these generations. iOS ties software tightly to Apple devices given the vertical hardware integration.
Google championed an alternative mobile ideology with Android – launched commercially in 2008. Based on the open source Linux kernel, Android allows greatly customized implementations across devices from various manufacturers. A set of Android Open Source Project (AOSP) components and APIs afford these variations.
The smartphone mass adoption wave left traditional OS vendors flat footed. Microsoft‘s early smartphone entries failed with consumers. Their last gasp Windows Phone OS ceased development in 2017 due to single digit market share.
Blackberry OS similarly collapsed under modern app-centric paradigms. Embedded OS variants continue thriving in niche device categories however – like cars, industrial controls and IoT. But classical PCs now comprise a minor portion of global operating system minutes.
Virtual and Augmented Reality OSes
Immersive computing introduces fresh OS considerations around 3D environments, new interface models and spatial awareness. Leading VR headsets utilize customized Android and Windows builds managed by parent company runtimes. OpenXR promises OS-agnostic VR/AR app development however.
Future immersive OSes may resemble today‘s video game engines – implementing advanced physics simulations, photo realism, sound propagation – facilitating believable interactive spaces beyond flat 2D GUIs. Machine learning assisted scene rendering and semantics may play integral roles.
The Road Ahead
Classical models will continue dominating the OS landscape short term. But radicalshake ups are certain long term from fields like AI, quantum and biomolecular computing. Russian startup NeuraLink exemplifies imminent potential: Their brain interface OS aims to expand cognition by networking neurons with cloud AI and knowledge bases.
Operating systems have progressed astonishingly since the 1950s – from handling simple tape drive pools to coordinating billions of thoughts per second across planet-scale networks. Similar exponential leaps in capacity and capability likely lie ahead. The full potentials of computing still remain largely unexplored at nature‘s most fundamental levels – where future OS innovation surely resides.
