Book excerpts:

The Z notation for specifying and designing software has evolved over the best part of a decade, and it is now possible to identify a standard set of notations which, although simple, capture the essential features of the method. This is the aim of this reference manual, and it is written with the everyday needs of readers and writers of Z specications in mind.

This is not a tutorial, for a concise statement of general rules is often given rather than a presentation of illustrative examples; nor is it a formal definition of the notation, for an informal but rigorous style of presentation will be more accessible to Z users, who may not be familiar with the special techniques of formal language definition.