VTAM@Mainframe Programming
VTAM (Virtual Telecommunications Access Method) is an IBM application program interface (API) for communicating with telecommunication devices and their users. VTAM was the first IBM program to allow programmers to deal with devices as "logical units" without having to understand the details of line protocol and device operation.
Creating an MVS mini system
It is mainly for safety. With a mini MVS system on disk you can re-IPL immediately in the case of a big crash

Planning your path from OS/390 to z/OS
Are you running OS/390 V2.6 or V2.7? Do you know IBM no longer supports these releases?

Catalogs - MVS Internals
Catalogs are used by MVS to locate datasets when a task attempts to allocate them without supplying their volume serial number.

Submit an Article
Here is an attempt to gather some interesting and highly recommended articles. It isn't a major directory and I have no intention of making it one....
Please read the disclaimer before reading the articles.