"No experience necessary" declares Jack D. Dennon to set you at your ease from the start.

He might add: "Large amounts of disk space vital", for CP/M Revealed requires you to sit at a micro and consult five other manuals.

But don't be daunted. Dennon aims for clarity, and he uses other sources to back this up. Even so, his description of a cursor in the opening pages might strike even the greenest as patronising.

He also has a tendency to show how but not why. This makes theoretical explanations mercifully brief but occasionally baffling.

For example, having mastered the cursor, you are led into a beginner's guide to Basic, which unaccountably lurches into commands that you might well manage to avoid for years.

But this is a practical book. Even step it takes can be mirrored on the screen. As the book progresses, Dennon warms to his subject and gives very lucid treatment to complex matters.

Where a comprehensive coverage of the options offered by CP/M would be too long, he sticks to brevity and points out where to find the full story.

But CP/M Revealed is as good as its word and is a book to spend time with.