IBM z/OS
A highly secure and scalable operating system for running mission-critical applications
Read the data sheet
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IBM® z/OS® is an operating system (OS) for IBM Z® mainframes, suitable for continuous, high-volume operation with high security and stability.

With IBM z/OS, you can use the computing power and resources of the IBM Z platform to help drive business transformation and accelerate innovation. Get the stable, secure environment your organization requires to improve performance for mission-critical workloads and meet future challenges.
What's new

Summary of updates for release V3.1

Explore past releases for IBM z/OS
Benefits AI-infused

Scale the value of data and drive digital transformation that is powered by AI and intelligent automation.

 Application modernization and simplification

Build new applications or modernize existing ones while optimizing and simplifying technology infrastructure.

 Cyber resiliency

Protect and thrive with unparalleled security and resilience capabilities with quantum-safe technologies.
Featured capabilities Simplified management

Improve z/OS programmer productivity with a web-based interface and streamlined, automated tasks.

 Explore z/OS Management Facility Server communications

Run multiple copies of z/OS as a single image, so you can manage multiple systems and resources from a single point of control.

 Explore Parallel Sysplex Faster recovery

Restore services and recover workloads substantially faster with zero increase in licensing costs. 

 Explore IBM System Recovery Boost Upgrade workflows

Enable and drive innovative development to support new hybrid cloud and AI business applications.

 Explore z/OS Upgrade Workflows Linux integration

Integrate popular open source packages, Linux® applications, IBM software and third-party software.

 Explore IBM z/OS Container Extensions Cloud provisioning

Simply create software service templates that provision IBM middleware for additional functionality.

 Explore IBM Cloud® Provisioning for z/OS JSON databases

Easily create and access JSON databases through a comprehensive set of C-based APIs.

 Explore EzNoSQL for z/OS Management services

Deploy services that streamline management tasks and apply best practices and internal standards.

 Explore z/OS Management Services Catalog IT resilience

Rapidly adapt and respond to disruptions or threats and continue operations without significant impact.

 Explore IBM Z resilience Pervasive encryption

Enable extensive encryption of data in-flight and at-rest to safeguard data and achieve compliance.

 Explore IBM Z pervasive encryption Simplified data archiving

Use serverless data movement and storage cloud communication to simplify data archiving in the cloud.

 Explore transparent cloud tiering
Supporting capabilities Workflow automation

Orchestrate configuration management, application deployment and provisioning IT tasks on z/OS.

 Explore z/OSMF Ansible Collection Container images

Download open source, no-cost container images that can run in Linux and zCX environments of z/OS.

 Explore IBM Z and LinuxONE Container Registry

User guides

Browse IBM Redbooks® user guides to get technical information about IBM z/OS capabilities. 
z/OS Introduction

The course covers z/OS access and interaction basics, data sets and data access methods and operating system environment topics.

Getting started with IBM z/OS Container Extensions (zCX)

Learn more about installing, tailoring and configuring zCX in your own environment.

Getting started with encryption

Understand how hardware and software components interact within a z/OS data set encryption environment.

What’s new in DFSMSrmm

See the latest enhancements to this fully functioning tape management system for removable media.

Getting started with zHyperLink

Find out how IBM zHyperLink for IBM z/OS makes it easy to accelerate transaction processing for the mainframe.

Getting started with IBM Z resiliency

Discover how hardware components and software components interact in a z/OS data set encryption environment.

Resources z/OS basic skills

Learn the basics of IBM z/OS including mainframe concepts, the value of the mainframe and the programs and capabilities of the operating system.

 z/OS language environment concepts guide

Read the guide to learn how to run C, C++, COBOL, PL/I Fortran and assembler apps.
Next steps

Explore add-ons for IBM z/OS to enhance the capabilities of your operating system.  

 Browse z/OS add-ons Contact a z/OS expert
More ways to explore Documentation Support IBM Redbooks® Support and services Global financing Flexible pricing Education and training GitHub community Community Developer community Business Partners Resources