IBM i: History and Timeline

If you’re confused about all the server and operating system name changes from System/38 to IBM Power, you’re not alone. Here’s a quick snapshot of the IBM server and operating system names through the years.

A Brief IBM i Overview

The simplicity, power, and reliability of IBM i is legendary. Today, there are more than 15,000 applications that run on this platform. It’s continually evolving, and yet it maintains support for proven applications written over 30 years ago that are still running critical business processes at organizations in every industry around the world!

IBM i (iSeries, AS/400) Timeline

IBM i History Timeline

IBM has changed the name of the operating system and the server quite a few times over the years, which has led to some confusion and heated conversations within the user community asking, “Is the AS/400 dead?” However complex, IBM’s changes were not without reason. Namely, to support evolving business needs for their customers, highlight new technology in the latest release, and make a distinction between this platform from others at IBM.

1978 System/38 CPF

IBM introduces System/38 as a midrange computer for general business and departmental use. The server uses an object-based operating system, laying the foundation for the IBM i we know today. This is where the work management concepts for controlling jobs on the AS/400 came from. System/38 also came with a relational database that we now know as Db2.

1983 System/36 System/36

IBM introduces System/36 as a midrange computer for general business and to service small businesses. This server was a flat file system and the main programming language was RPGII.

1988 AS/400 OS/400

The IBM Application System/400 midrange computer—affectionately known to many as the AS/400—replaces the System/38 and supports System/36 in a runtime environment. The new AS/400 platform extends the System/38 architecture of an object-based system by adding an integrated, relational database known as Db2. It retains the object-based operating system, renamed OS/400, and its virtual machine and single-level storage concepts establish the platform as an advanced business computer.

For a deeper dive into the AS/400 years, please reference the “A Brief History of the IBM AS/400 and iSeries” PDF from IBM.

2000 iSeries OS/400

IBM introduces a new generation of servers to help manage the unprecedented needs of e-business. The AS/400 is rebranded as the eServer iSeries.

2006 System i i5/OS

The iSeries server is renamed IBM System i, distinguishing it from System p hardware, which runs AIX and Linux. The operating system name is called i5/OS. System i with the i5/OS operating system is positioned as an “all-in-one” Windows alternative for small and medium sized businesses.

2008 IBM Power Systems IBM i

IBM integrates the System i and System p platforms into a single, unified server called Power Systems (shortened to IBM Power in 2021), which now supports the IBM i (formerly i5/OS) and AIX (UNIX) operating systems, layering in Linux in 2012. This move coincides with the IBM i 6.1 release, again changing the name of the operating system and shifting the naming convention from V5R4 to 6.1.

It offers a built-in database (DBMS, DB2/400), a menu-driven interface, multi-user and dumb terminal (IBM 5250) support, printers, security, and communications. It also offers web-based applications, which can be executed inside the IBM WebSphere application server (optional), or in PHP/MySQL using the Apache web server.

Everything is a file in UNIX systems. Everything is an object on IBM i. IBM i now offers UNIX-like file directories using the integrated file system (IFS) and Java compatibility through the Java virtual machine. Flash forward to today, where customers can even develop using open source technology like Git, Python, PHP, and more.

IBM i in the 2020s

The annual IBM i Marketplace Survey Results show organizations clearly seek to maintain this technology over the long term as evidenced by their continued investment in performing system upgrades and keeping up with the current hardware.

IBM i in the Data Center: Staying Current

Milestones in IBM i Operating System History

IBM releases a new operating system level about every two or three years. In between new operating system levels, IBM releases Technology Refreshes (TRs) to support new hardware features and to ease our burden of always chasing new OS levels, which is hard on change control teams. The roadmap for IBM i continues into 2032 and beyond, according to Steve Will, chief architect of the IBM i operating system at IBM, which is great news for those of us on the platform!

IBM i V5R4 February 2006 September 2013
IBM i 6.1 March 2008 September 2015
IBM i 7.1 April 2010 April 2018
IBM i 7.2 November 2014 April 2021
IBM i 7.3 April 2016 Still supported
IBM i 7.4 June 2019 Still supported

More information available here along with extended support information: and

Helpful IBM i 7.4 Resources

Milestones in IBM Server History

Fundamental features of the IBM i operating system have existed since the System/38 days. From the beginning, it was made with business applications in mind. This system was built so that the hardware could evolve while business applications ran, with little or no interruption.

Power6 June 2007 March 2019
Power7 February 2010 September 2019
Power8 June 2014 Still supported
Power9 February 2019 Still supported
Power10 September 2021 Still supported

More information available here:

Helpful Power10 Resources

The IBM i Story at HelpSystems

HelpSystems shares IBM's long history of success thanks to this power platform. Our software now secures and monitors IT environments, provides high availability, automates processes, and gives easy access to the information people need at thousands of organizations in hundreds of countries around the world.