Mainframe & COBOL Glossary
Decoding the language of the world-s most powerful systems. From z/OS architecture to modern bridging technologies.
Operating System
z/OS
The primary 64-bit operating system for IBM zSystems. It is designed to offer high availability, security, and scalability for mission-critical applications.
LPAR
Logical Partition. A subset of a computer-s hardware resources, virtualized as a separate computer.
IPL
Initial Program Load. The process of loading the operating system into the computer-s main memory (the mainframe equivalent of "booting").
Sub-Systems
CICS
Customer Information Control System. A high-performance transaction server that runs large-scale business applications.
IMS
Information Management System. A joint hierarchical database and information management system with extensive transaction processing capabilities.
DB2 for z/OS
IBM-s premier relational database management system, optimized for the high-availability requirements of the mainframe.
Programming & Data
COBOL
Common Business-Oriented Language. A procedural language designed for business data processing, still powering 80% of global financial transactions.
JCL
Job Control Language. A language used on IBM mainframe operating systems to instruct the system on how to run a batch job or start a subsystem.
VSAM
Virtual Storage Access Method. An IBM disk file storage scheme used in mainframe operating systems.
Security & Processing
RACF
Resource Access Control Facility. The primary security software for z/OS, managing authentication and authorization.
zIIP
z Integrated Information Processor. A specialty processor used to offload specific workloads (like Java or XML) to lower total cost of ownership.
EBCDIC
Extended Binary Coded Decimal Interchange Code. An 8-bit character encoding used primarily on IBM mainframe and IBM midrange computer systems.
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