Looks to be an older edition (copyright of 1978). It is probably a guide and/or reference for a professional programmer or student. This description may be from another edition of this product.
I haven't read the whole thing as yet. But so far, I find it easy to read. It starts with simple concepts of the IMS/DL1 gradually building to more advance concepts of the system.
ThriftBooks sells millions of used books at the lowest everyday prices. We personally assess every book's quality and offer rare, out-of-print treasures. We deliver the joy of reading in recyclable packaging with free standard shipping on US orders over $15. ThriftBooks.com. Read more. Spend less.