The Sinclair Spectrum In Focus is probably the best of all the books I have looked at in this issue. Suitable for all Spectrum users, from beginners to those who already have some programming expertise and perhaps, too, programmers of other machines!

It is not a simple book and does not betittle difficult topics, but its achievements are worthy of a little study. Neither is it a book aimed at academics, for while Mark Harrison's handling of topics can be analytical and mathematical, he has taken care to assume little and explains new theory in a precise, logical and understanding fashion. On completion, the reader should have knowledge of the principles of a computer system, number systems used by computers, flow charts, Spectrum Basic and logic, control statements and functions, an understanding of graphics and colour and their use in screen displays, to mention only a few. To add to this there is a list of good quality games and utility programs.

Well illustrated, legibly printed and well explained throughout its 180 pages, The Sinclair Spectrum In Focus is highly recommended.

Published by Sigma Technical Press, The Sinclair Spectrum In Focus is written by Mark Harrison and costs £6.25. ISBN 0 905104 28 5