IBM mainframe computers are servers based on the processor instruction set of the System/360 introduced in the mid-1960s, much as today's Intel computers and processors are based on the 8086 used in the original 1981 IBM PC. This category covers the operating systems (OSs) and software products that run on IBM mainframes. Any sites also including mainframe hardware-related information belong in a subcategory of Computers/Hardware/Systems/IBM
On this page, OSs are arranged in two groups and levels: 1) Top group: issues spanning multiple IBM OSs. 2) Bottom group: specific IBM OSs, individual instances; there is only one OS of this name/type, with its own category.
This category and its subcategories are for websites that cover the operating systems (OSs) and software products that run on IBM mainframes. Any sites also including mainframe hardware-related information belong in a subcategory of Computers/Hardware/Systems/IBM
Only sites that do not fit in one subcategory go here. For example, many sites discuss z/VM and VSE/ESA, as both are often used together on one mainframe.
Mainframe application software developers are listed in Computers/Companies/Software_Development/Mainframes.
Free IBM mainframe-related software that is available for direct download from the Web site or is delivered to you after you contact the owner. Some sites require free registration.
Functional software, not just code snippets. URLs within web sites listed elsewhere in dmoz are permissible, but they should provide links or direct access to all of the mainframe freeware on the site. Please do not include sites that only offer software that expires after a given period of time.
Software that runs on other platforms, but accesses a mainframe, will also be considered.
Sites offering software that runs on IBM mainframe computers, from financial applications to system utilities.
One major exception to the requirement that the software run on the mainframe is software that interfaces to the mainframe, such as 3270 mainframe terminal emulation software that runs on Windows- or Unix-based workstations but is used to connect to the mainframe.
For software companies that sell predominantly non-mainframe software, it is preferable to list a Web page other than the home page, if one exists that links to all mainframe software products.
If in doubt as to which source of software should be listed here, select the site where support is provided for the software worldwide. Not resellers or local distributors. Generally, the manufacturer.
Offerings of free software, not demos or time-limited copies, should be listed in Computers: Software: Operating Systems: Mainframe: IBM: Freeware.
z/OS is the latest in a long history of names for the high-end IBM mainframe operating system that began as OS/360 in the mid-1960s on the System/360. The most recent previous names were OS/390 and MVS.
This category is for websites that involve or cover the IBM mainframe computer operating systems: z/OS, OS/390, all versions of MVS and even OS/360 and its immediate successors. And its components, including Unix System Services (USS).
z/VM is the new name for IBM's VM/ESA mainframe operating system. ESA (Extended Storage Addressing) is a feature added to S/390 operating systems (MVS, VSE, VM) to allow addressing beyond the 16MB limit.
This category is for websites that involve or cover the IBM mainframe computer operating systems: VM, VM/ESA, z/VM.
z/VSE is one of IBM's mainframe operating systems. It originated as DOS/360 on the low-end System/360 computers of the mid-1960s.
Sites that also discuss other operating systems are found in Computers/Software/Operating Systems/Mainframe/IBM. Sites that also discuss hardware are found in a subcategory of Computers/Hardware/Systems/IBM.
This category is for web sites that involve or cover the IBM mainframe computer operating systems: DOS, DOS/VSE, VSE, VSE/SP, VSE/ESA and now z/VSE.