This book may be used as a self-contained manual for BBC-BASIC, the main language of the BBC Microcomputer and Master Series Computers. Information is presented in a form handy for reference. Page 163, for example, tabulates all characters in the ASCII range; pages 124-5 summarize all information needed when composing screens of MODE 7 graphics. A quick reference to all functions and operators is given on page 179; the syntax of every statement and command of BBC-Basic is summarized on pages 180-1. But there is more to this book. How do you make a computer sort names into alphabetical order? Not as obvious as it might seem. Three different sorting techniques are explained by example in this book: bubble sort, monkey puzzle (more formally the 'binary tree') and Quicksort relies on 'recursion' - an important programming concept which is explained and demonstrated. Making coloured objects rebound around the walls of a squash court is another technique demonstrated; so is making voices sing in harmony; so is computerizing a humble address book.