This book's shot straight to the top of my 'what did I ever do without it' list. Steve Kramer has really taken on a mega task in trying to explain the inner workings of the Spectrum's operating system - and he's done a tremendous job.

The first few chapters provide a gentle introduction on how to use some of the ROM's most useful routines. You'll find out about printing techniques, scanning the keyboard, clearing and scrolling the screen and how to control the PLOT, DRAW and CIRCLE commands, plus an in depth look at the cassette routines.

Enough there to fill a whole book, but there's much more. Interface 1 is next for the full treatment. When it was launched it really increased the power of the Speccy but the extra facilities that it offers have never yet been fully explained - until now that is. This book gives one of the best breakdowns of the new 8K ROM that I've ever read and, what's more, it's written in plain English. There are full details of how to use all the ROM routines, to control the micro drives, the network and the RS232 port. In fact, it'll tell you all you could ever want to know about the shadow ROM - but didn't know who to ask.

Steve Kramer also steers a course for you through channels, streams and ports. As well as showing what attaches where, he manages to make the whole subject of I/O ports fun with a program that produces speech by digital recording.

You've probably got the idea that I'm impressed - and you'd be right. This is one mega task that has been brought to mega conclusion. Check it out.