Mainframes are computers

At their core, mainframes are high-performance computers with large amounts of memory and processors that process billions of simple calculations and transactions in real time. The mainframe is critical to commercial databases, transaction servers, and applications that require high resiliency, security, and agility.


How do mainframes work?

IBM® mainframes are uniquely engineered to:

  • Run common operating systems like Linux® – as well as specialized operating systems such as z/OS® –  along with software that takes advantage of the unique hardware capabilities.
  • Support massive simultaneous transactions and throughput (I/O) with built-in capacity on demand and built-in shared memory for direct application communication.
  • Deliver the highest levels of security with built-in cryptographic cards and innovative software; the latest IBM Z® systems can execute up to 1 trillion secure web transactions per day and manage privacy by policy.
  • Offer resiliency through multiple layers of redundancy for every component (power supplies, cooling, backup batteries, CPUs, I/O components, cryptography modules) and testing for extreme weather conditions.

What does a mainframe look like?

Today’s mainframes are much smaller than the early “Big Iron” machines. With a standard 19” rack, the latest mainframe seamlessly coexists with other platforms in the data center. One IBM z15™ single-frame system requires 75 percent less floor space than x86 2U servers running the same workloads and throughput – and reduces power consumption by 40 percent.

Who uses IBM mainframes?

While many of the world’s top companies use mainframes, these systems are made for businesses of all sizes – and are available through public, private or hybrid cloud.

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Banks: Allied Irish Bank uses the agility of the IBM Z® platform to deliver open banking and new functionality.

Government agencies: The Department of the Treasury of Puerto Rico deploys a continuous availability solution to ensure maximum uptime.

IT service providers: Emid delivers a software platform on IBM Z and gains simplicity, resilience, data privacy and security.

What does a mainframer do?

Mainframe developers are in high demand, with starting salaries that are higher than most other college graduates.

Torrie McLaughlin

Torrie explains her journey from veteran and librarian to COBOL programmer.

Alex Stuart

Alex describes how he is “splunking the mainframe.”

Meghan McGrath

Meghan shares how she helped bring 100% encryption to the mainframe.

How can you get started on the mainframe?

Get hands-on learning: Use this learning system to go from a novice to a skilled mainframer.

Create an app: Use these tutorials to create an app that accesses the mainframe.

Try software: Try mainframe software at zero cost, and with no installation required.

What’s new and next for the mainframe?

The core design values of the mainframe have always been reliability, scalability, compatibility, and security.

Today’s mainframe is designed with next-level data privacy, enterprise security, and cyber resiliency – all delivered through a hybrid cloud.


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