What is IBM i?

Learning Objective

By the end of this lesson, you will understand what IBM i is, what makes it different from a typical server operating system, and how it relates to older names you may have heard, like AS/400.

Simple Explanation

IBM i is an operating environment that runs on IBM Power Systems hardware. The word "environment" matters here: instead of installing an operating system, a database, security tools, and a job scheduler as separate pieces and connecting them yourself, IBM i bundles all of that together into one integrated platform.

Out of the box, IBM i includes:

• An operating system that manages the hardware and runs programs
• DB2 for i, a relational database built directly into the platform
• Object-based security that controls who can do what, down to individual pieces of data
• Job and work management, which controls how programs run and share system resources
• A development and runtime environment for building and running business applications

Because these pieces are designed to work together from the start, rather than bolted on afterward, IBM i is often described as an "integrated" platform rather than just an operating system.

If you have only used general-purpose operating systems before, this "everything included" approach is the biggest mental shift when learning IBM i.

Why It Matters

IBM i is not a legacy curiosity. It runs core, business-critical systems for organizations around the world today: order processing, inventory management, financial systems, manufacturing, distribution, healthcare records, and government services, among others.

Many of these organizations have relied on IBM i for decades because it has a strong track record for reliability and long-term stability. That same reliability is exactly why IBM i can feel "invisible" - it quietly keeps running in the background, so newer developers sometimes never hear about it until they encounter it directly on the job.

For you, that means two things. First, if you are new to IT, IBM i skills are genuinely useful in the job market, particularly in industries where these systems are deeply embedded. Second, if you already work with IBM i, understanding it as a coherent platform - rather than a collection of unrelated tools - will make everything else you learn about it click into place faster.

Practical Example

Imagine a mid-size distribution company that ships products to retail stores. Every day, the company needs to:

1. Receive new sales orders
2. Check current inventory levels
3. Update stock as items are picked and shipped
4. Generate invoices for completed orders

On many platforms, this would require separately installed and configured software for the database, the application server, security policies, and job scheduling, all maintained by different tools.

On IBM i, the same company could run all of this using programs that read and write directly to DB2 for i (the built-in database), while the platform's security model controls exactly which users and programs can view or change order and inventory data, and its job management features control how those programs run throughout the business day. The pieces are not separate products glued together after the fact; they are part of the same platform.

This is a simplified, illustrative example rather than a real system, but it reflects the kind of work IBM i is commonly used for.

Common Confusions

"Isn't this the old AS/400? Is it still around?" Yes and no. AS/400 was the original hardware and software platform, first introduced in 1988. Over the years, the platform was renamed and modernized: AS/400 became iSeries, then System i, and today the operating environment is called IBM i, running on IBM Power Systems hardware. Many people who have worked with this platform for a long time still say "AS/400" out of habit, the same way some people still say "dial a phone number" long after rotary phones disappeared. When you hear AS/400, iSeries, or System i, you can generally assume the person means what is now IBM i.

"Is IBM i the same thing as IBM Power Systems?" Not quite. IBM Power Systems refers to the physical hardware (the servers) that IBM i runs on. IBM i is the operating environment that runs on top of that hardware. The same Power Systems hardware can also run other operating systems, but IBM i is the platform this course focuses on.

"Is IBM i just a database?" No. DB2 for i, the built-in relational database, is a core part of IBM i, but it is only one piece. IBM i also includes the operating system itself, security, job management, and the runtime environment for applications. Thinking of IBM i as "just a database" misses the fact that it is a complete, integrated platform.

Quick Recap

• IBM i is an integrated operating environment that runs on IBM Power Systems hardware.
• It bundles the operating system, the DB2 for i database, security, job management, and an application runtime into a single platform.
• IBM i is the modern name for a platform previously known as AS/400, iSeries, and System i; many people still call it AS/400 out of habit.
• IBM i (the platform) and IBM Power Systems (the hardware) are related but distinct.
• IBM i is far from obsolete: it runs business-critical systems for organizations around the world today.

Try Asking the AI Tutor

Use the AI Tutor to ask follow-up questions about this lesson. For example, try asking:

• "What is the difference between IBM i and IBM Power Systems?"
• "Why do people still call IBM i the AS/400?"